Bowling Tomy Pocket Game

@john2001plus

0 seconds ago

It is like a bowling slot machine.

How Small Can a Video Game Actually Be?

 

 @john2001plus 

3 minutes ago (edited) 

This video describes my early game programming days, starting with very primitive 8-bit computers.

3D Escape 1000 Mazes by Entex

These Arcade Games DON'T Make Any Money?!

https://www.youtube.com/watch?v=umEpMKRjk-c

Massive 1966 Sega Periscope Arcade game. Firing Torpedo's is fun!

Never saw this one.  I would have loved it.

I remember playing a standup periscope game in the late 1960s, and I loved it.  I would have been around 9 years old.

It was the first arcade game I played, and it was in a long-gone pizza shop near the river in Madison, Indiana.  

I would take a bigger interest in arcade games in the 1970s.  First was a really lousy racing game (https://www.youtube.com/watch?v=09D8tek091s) in a "dime store" in downtown Columbus, Indiana.  Then I found a mechanical shooting game I liked at a department store.  Then my sister and I became hooked on a mechanical baseball game that was in one of those really small corner grocery stores.

Apparently, arcade games have a long history.

Columbus got its first mall around 1973, and an arcade opened a year later, which changed my life forever.  The arcade started with mechanical games.  The first video game was Pong, which I didn't find very interesting.

I Played 15 Atari 5200 Games YOU Recommended

10 MORE Atari 5200 Games You Recommended

The 20 Greatest ColecoVision Games of All-Time

ColecoVision | The 25 greatest games

Turbo is a questionable #1 choice. Compared to other driving games, it has a fixed perspective. I'd rather being playing Pole Position, which gives a better 3D effect. I am such a Donkey Kong fan, it would have been one of my top choices. The Q-Bert game shown appears to be Q-Bert Qubes.

Donkey Kong (Coleco Handheld)

This would have been fun to play.

Konami Code on an Arcade1Up Ms. Pac-Man?

@john2001plus
3 minutes ago (edited)
Ms. Pac-Man started as a third-party hack of the original Pac-Man called Crazy Otto. As a result, the original Pac-Man maze exists inside the original Ms. Pac-Man, but there is no apparent way to play it.

In the early 1980s, I started a game of Ms. Pac-Man and somehow got the Pac-Man maze for the first screen. This bug was likely very rare because I have never heard of anyone else seeing it. Maybe the glitch was unique to the machine I was playing. In very rare cases, a RAM bit will get flipped or misread, resulting in a bug.

(Chat GPT found a story of one other person encountering the same bug of getting the Pac-Man maze on Ms. Pac-Man.)

The Anniversary Arcade version of Ms. Pac-Man/Galaga had a secret code to play the original Pac-Man game.  There was even a bug where you could play the attract mode of Galaga for a while.

I would really like it if I could play Pac-Man on my Ms. Pac-Man Arcade1up.

This Vectrex does things I never thought possible

10 Essential Games for ColecoVision

The Best 2600 Game, Period

Top 10 Favorite Atari 2600 Games

Nintendo Just STOLE Switch Games You DIGITALLY PURCHASED

SPIDER FIGHTER for Atari 2600

Atari 2600 Keystone Kapers from Activision

WHAT THE HELL IS HAPPENING TO VIDEO GAMES?!

https://www.youtube.com/watch?v=D7rZcrXx2FE

@john2001plus
1 minute ago
In the 1990s, game consoles were distinct entities from PCs.  Now game consoles are close enough to PCs that it makes more sense to buy a PC.  To be viable, the consoles have to offer some kind of value, like the XBox Series X did for $500, which was considerably cheaper than the equivalent gaming PC.  The low price was achieved through custom hardware and mass production.

Atari is still making 2600 games

Cross Force (Atari 2600)

The $10,000 Trinitron

No matter how good this TV was in 1981, the technology was still limited to 480i. I'm not sure if 480p was even possible at the time. When DVDs were introduced in 1996, they were still 480i.

No matter how high-tech the TV claimed to be, it still had the same fundamental limitations.

The computers that existed in the early 1980s generally output a 240p signal, although a few machines had options for higher resolutions.

In the 1990s, a friend of my mother's was showing off her 33-inch CRT TV. She asked me how much I thought it cost. I correctly guessed $3,000. Soon, however, that expensive TV would become obsolete as HDTV came along. Some of the final CRT televisions could accept an HD signal before flat-screen TVs became common.

In my final years in Utah, I saw someone giving away a 33-inch TV on the curb. I thought maybe I could use it as a video game display. It was so heavy—probably around 150 pounds—that a friend and I nearly killed ourselves trying to lift it together. I eventually had to give it away before I moved.

Shortly after arriving in Indiana, I saw another 33-inch TV sitting on a curb. I convinced the owner to haul it to my house. Again, I wanted to use it as a video game display, but I eventually gave it away. A young couple wanted it for their son's video game system.

Atari's Star Wars Cabinet Easter Egg

First Conan Video Game Found! Conan the Great

Heavyweight Champ (Arcade) | 1976 Arcade Gaming

Is it Practical to Stream Video Games?

This is an update to an article I wrote five years ago...

Roughly 36 years ago I had an argument with a coworker. He argued that once internet speeds became fast enough to transmit full-screen video, we wouldn't need game consoles, since we would be able to stream video games from a server to our computer screens. Rather than pay for expensive hardware, that hardware could be on a server someplace, saving us money.

I have to admit that he had remarkable foresight literally 30 years ahead of his time. This was at a time when the Internet was text only. However, I saw a number of problems with his idea...

1. Internet speeds were still fairly low, like 1,200 to 2,400 bits per second.

2. Latency is always an issue when playing games. No matter fast your Internet is, there is an overhead to transmitting data back and forth.

 
3. It is always advantageous to have your own hardware. Imagine having to share hardware with other people competing for the same physical resources. I figured that hardware would get cheaper over time, eliminating the need to share hardware with other people.

4. His idea reminded me of the early days of computing where you would have to dial into a mainframe using a *dumb terminal*, which I actually owned and used at the time, whereas the new trend in computing was for everyone to have their own computer.

I argued that streaming video games would *never* be practical. He couldn't understand why I didn't see the obvious wisdom of his idea.

Seven years ago Google introduced Stadia, which was a video game streaming service, and it totally flopped. Other companies like Microsoft and Amazon worked on the same idea, but they all suffer from the same problems like latency.

 
It makes very little sense to be dependent on unreliable Internet communication and shared hardware to play games when you can purchase a video game console like the Xbox Series X for $500*. Putting hardware in a centralized location instead of your living room isn't necessarily cheaper, except that you can share that hardware with other people, but what if everyone wants to use the hardware at the same time?

In theory, this could become practical someday, but the same technology that will make this more feasible will also make it more feasible for you to have your own hardware that is just as good. This is the problem I saw three decades ago

* Now $798.

The Thing You Can't Defeat - DOOM's Creepiest And Most Depressing Mod

I tried playing this. It is like the original Doom, “Knee-Deep in the Dead,” but each new map gets weirder, more distorted, and more annoying. The music is creepy. I quickly gave up because I don’t play Doom to be annoyed.

The WAD does some clever things. It can instantly transport you to another identical area that looks different. So, as you exit an area that you just visited, the textures are now different, and you are left wondering, “Why do things look different?” Or, as I exited an area, I was suddenly in a different part of the map. In one of the maps, I suddenly found myself playing the next map, as if I had forgotten that I had finished the last one.

The Gaming Market is Starting to Break

Changes (Arcade)

Space Fury Arcade Cabinet MAME Gameplay w/ Hypermarquee

@john2001plus
2 minutes ago
It is sort of a combination of Moon Cresta, Bosconian, and Asteroids Deluxe. I prefer Moon Cresta.

Cat'n Mouse (Arcade)

TNT Evilution (100%) Walkthrough (Map30: Last Call)

@john2001plus
1 minute ago
I just finished Final Doom on "Hey, not too rough".  Because of the complexity and difficulty of this game, I think that I need more practice before I move to a harder level.  However, I could just jump into "Hurt Me Plenty" and see what happens.

I have been alternating all the maps in Doom, Doom II, and Final Doom for months.  I love playing this game, but I think that I need more variety, so I'll be looking at what else I can play.  Maybe a different Doom WAD.

The Bounty (Arcade)

THE DIFFICULTY OF FINAL DOOM

Tank 8 & Arcade Video Games in 1976

The Pac-Man Game You Never Played

Atari Had ONE Great Idea for This Snoopy Game

Night Driver & Arcade Video Games in October 1976

Birdie King (Arcade)

@john2001plus  11 minutes ago

I remember playing Birdie King, maybe just once. 

In 1985, I played the Bally Mini Golf which I loved.

Multitasking on a Z80 CPU

https://www.youtube.com/watch?v=tMYGlYO3v9U

@john2001plus
0 seconds ago
I programmed games on a couple of different Z80-based systems. The traditional approach is to have a game loop that calls several functions inside the loop. Each function checks whether it needs to update something and performs the update only if necessary.

The Moment Gaming Stopped Trusting Players

Sony Has Spoken. This sucks. I’m not happy

The End of Physical Media

No Escape! on the Atari 2600 - The MASHUP You Didn't Know You Needed

Atari 2600 (It's Better Than You Think)

Bachelor Party

Azurian Attack

The Plutonia Experiment (100%) Walkthrough (Map32: Go 2 It)

@john2001plus

3 months ago
WTF. I played Plutonia Map 32 on "I'm Too Young to Die," and it was a nightmare. The arch-viles kept resurrecting enemies, and I had to kill multiple cyberdemons. I left maybe five of them alive when I hit the exit and still got 98% kills.

I had to keep saving my progress incrementally just to get through it. The map left me with a stress level that honestly feels detrimental to my health. I can't imagine playing it on a tougher difficulty.

@john2001plus

0 seconds ago
I managed to barely get through this map on the second level of difficulty.  Just like my "I'm Too Young to Die" experience, I had to exit before I got 100% of the kills.

I tried to get the monsters to infight in the big area, and this really saved my bacon.  Eventually, I had to do some almost suicide-runs against the Cyber Demons.

There are too many "peek-a-boo" attacks in this map.  You have to do it constantly.  This becomes tedious.

Due to the extreme difficulty of this Wad, I'll probably stick to the second level of difficulty on my next playthrough.

Azurian Attack (Arcade)

This is Amazing! Zaxxon Arcade on Atari 2600

This is what happens when you put a CPU on a 2600 cart.

Astro Pinball

@john2001plus5 minutes ago (edited)

10:43 The attract mode looked really fun, but the actual gameplay seems to have problems. That lower bumper blocks most of the angles that you could shoot. 

Having worked in the videogame industry, I know that companies are more concerned with making release dates than they are with quality.

Galaxian Atari 2600 Livestream Casual

Swoop (BBC Micro)

Zoo Keeper (Arcade)

Air Raid (Atari 2600)

Astro Navigator (BBC Micro)

My Reaction to Completing Final Doom

I just finished TNT Evilution on the "I'm too young to die" difficulty. I enjoyed this perhaps more than The Plutonia Experiment, which starts with some dull maps and the secret maps were ridiculously difficult even on the easy difficulty. My stress levels playing those maps were at an extreme unhealthy level.

I asked ChatGPT what it thought of this, and it came up with...

'That’s a pretty reasonable take—and honestly, you’re not alone.

TNT: Evilution vs. The Plutonia Experiment comes down to very different design philosophies:

• TNT: Evilution leans more toward atmosphere, exploration, and gradual escalation. Even when it’s challenging, it usually gives you space to breathe.
• Plutonia is basically a gauntlet. It was designed by the Casali brothers to punish mistakes—tight encounters, lots of traps, and enemies like Arch-Viles and Chaingunners placed to maximize frustration.

What you felt with Plutonia—high stress even on easy—is kind of the point of that megawad. But that doesn’t automatically make it more fun. There’s a difference between:

• engaging challenge (TNT often hits this), and
• constant pressure with little recovery time (Plutonia at its worst)

Your comment about the secret maps is especially telling. Plutonia’s MAP31 and MAP32 are infamous for being brutal regardless of difficulty. On “I’m Too Young to Die,” you get more ammo and take less damage, but the encounter design itself doesn’t fundamentally change—so the stress is still there.

Also worth noting: early Plutonia maps do feel oddly flat compared to what comes later. It ramps up hard, but not always smoothly.

If your stress was at “unhealthy levels,” that’s a good signal—not a weakness. Doom is at its best when you’re in that flow state: alert, but not overwhelmed. Once it tips into constant tension, it stops being fun and starts feeling like work.

If you’re continuing with classic Doom content, you might enjoy:

• Final Doom TNT on higher difficulties (it scales more gently)
• Community WADs that emphasize exploration over ambush spam
• Or even revisiting Plutonia later with foreknowledge—it becomes more of a puzzle than a panic simulator.

Stargunner (Atari 2600)

Monster Inn (Tomy Tutor)

@john2001plus6 days ago (edited)
Monster Inn gives me Popeye vibes, but it looks like much less fun. The movement looks jerky.

This "100,000 Games" Console is a TOTAL SCAM...

ICBM Attack (Bally Astrocade)

Terminator: The Story of the 6502 Code You See Onscreen

https://www.youtube.com/watch?v=NebvccLHutQ

@john2001plus
The 6502 was a very simple chip, but it was cheaper and faster than other 8-bit chips.

I loved programming the 65816 on the SNES.    I wonder how the world would be today if we got 32 and 64-bit versions of the 6502?

BATTLEZONE on Atari 2600 | Tank Combat in the FAR Future of 1999!

@john2001plus
0 seconds ago
Battlezone is one of my favorite Atari 2600 games.

However, it is hard to get a good score.

My other favorite Atari 2600 games include Boing!, Pac-Man Jr., and Pole Position.

Tank 8 & Arcade Video Games in 1976

The Problem Mario 64 Created

Bomb Man (Tomy Tutor)

4:24 These simple 3D mazes are easy to write; they can even be done in BASIC. I experimented with this kind of maze, but never turned it into a full game. I wrote more complex 3D effects on both the TS1000 and TS2068, but since they were in BASIC, they took forever to render. On the TS1000, I created a rotating oscilloscope with a 3D projection. I did this on the TS2068 as well. On the TS1000, I was able to animate it by storing 16 screenshots in memory and switching the screen pointer. It looked incredible. On the TS2068, I implemented a kind of ray casting that created a 3D chessboard with an infinite number of squares projected out to the horizon. I also created a 3D pyramid projected in a 2.5D isometric view. Unfortunately, I sold all of these effects—along with some simple BASIC games—as a product called The Great Game and Graphics Show. It sold well, but in hindsight, it was closer to a demo than a fully realized product. It was 1984, and I was just getting my feet wet writing software for personal computers.

68000 - The CPU ahead of its time

I found the 68000 easy to program.  The instructions are very straightforward.  i.e. move 8, 16, or 32 bits to a register.  Add two registers.  Move 8, 16, or 32 bits to memory.  It is almost as easy to follow as C code.

Likewise, I found the Z80 easy with its many 16-bit registers.  The 6502 has few registers, which is more difficult to program.  However, the 6502 has a trick, which is zero page instructions that use fewer clock cycles to access the first 256 bytes in memory.  Programmers can use the zero page like registers.

The Plutonia Experiment (100%) Walkthrough (Map30: The Gateway of Hell)

@john2001plus
5 minutes ago (edited)
I finally finished The Plutonia Experiment on "I'm too young to die."   The game is no cakewalk on the easy level of difficulty.  The secret map 32 and the final map 30 are highly stressful.

This is a very imaginative and enjoyable set of maps.  I like them better than the more mundane Doom II maps.  This is what Doom II should have been.

Q*bert: What's He REALLY Saying When He Gets Killed?

Video games did look better when we were kids

When British Devs Don't Understand American English

The Plutonia Experiment (100%) Walkthrough (Map32: Go 2 It)

@john2001plus
1 second ago
WTF. I played Plutonia Map 32 on "I'm Too Young to Die," and it was a nightmare. The arch-viles kept resurrecting enemies, and I had to kill multiple cyberdemons. I left maybe five of them alive when I hit the exit and still got 98% kills.

I had to keep saving my progress incrementally just to get through it. The map left me with a stress level that honestly feels detrimental to my health. I can't imagine playing it on a tougher difficulty.

Doom 64 (N64) Was Overlooked & Underrated

Never Do THIS in Super Mario Bros... 🚫

I Thought Tempest Was Hard—Then I Tried to Build an AI for Robotron

Beneath Apple Manor: Special Edition

The Incredible Evolution of Computers

I like the video.  Unfortunately, it is just the first part of four.

The first microprocessor, the 4-bit Intel 4004, was created for Japanese companies that wanted to make the first electronic calculators.  I have seen 4-bit devices used for cheap electronics, like low cost chess playing computers.

In the first half of the 1980s, 8-bit computers were the norm, with the Apple II costing up to $1,300, and the IBM models costing considerably more.  The Atari 800 started at $1,000, and the Commodore 64 started at $595, which adjusted for inflation would cost $1900 today.

Sinclair, along with Timex, were offering budget models that created a dedicated fan base.

In the second half of the 1980s, the industry was moving to 16-bit, so the 8-bit models were being heavily discounted.  The C64 sold for $100 or less.

The 1990s saw a slow transition to 32-bit computers, and the 2000s saw a slow transition to 64-bit.  There is almost no reason to go to a higher number of bits, except for graphics cards that range from 64-bit to 384-bit.

Exploring Doom's Unholy Cathedral - An Unholy Mess?

@john2001plus

0 seconds ago
I really like the map. The teleport system is annoying, but once you learn where they go, the map has many rewards.  

Space Fury

Doom 2's Most FRUSTRATING Level

@john2001plus
0 seconds ago

It is possible to get to the "red brick area" from the outside, at least on the PC version.

The key to The Citadel is the room with the five transporters arranged in a square, with one in the middle. The four corner transporters take you to one of the four corners of the citadel, most of which you have to visit. Once I understood this, navigation became easier. Initially, the map seemed like a confusing maze with no clear purpose. It still feels that way, but it is not as hard to navigate once you understand the layout.

I start the map by running around the outside, killing as many enemies as I can. I try to take out the monsters in the windows; otherwise, I will have to deal with them later when I am inside. I find the outside more interesting than the inside.

Although the map at first seems like a poor level, I am kind of glad it is in the game. There are enough interesting things about it to make it worth playing.

In general, Doom II maps tend to be larger, more confusing, and filled with more ambushes. This can be frustrating, but it also offers more of a challenge.

Sokoban (NEC PC-8801 & Fujitsu FM-7)

Penetrator (ZX Spectrum) - Z80 Block Copy is slow

https://www.youtube.com/watch?v=-AvJFKq3gC4&t=461s

@john2001plus
3 days ago (edited)
7:41  I played this game on the Timex-Sinclair 2068, which I purchased around the beginning of 1984 or the end of 1983.   The TS2068 isn't necessarily compatible with Spectrum games, but it could have been a port.  Maybe the sound was better because the 2068 has a sound chip.

If you did well, you got a fireworks show at the end.  We see this in the video, but I thought it was better with sound.

I may have played with the keyboard, which is how I usually played games.

The barrier on level 5 appears to be the end of the game.  I remember this now.

Given the hardware, I'm impressed with the scrolling.  I was impressed in 1984 because the block memory copy on the Z80 processor is super slow, which is how you would scroll the entire screen, although I can think of some coding tricks to do a slightly faster memory move.


@chronologicallygaming
14 hours ago
Great memories—and you're spot on. The TS2068's AY sound chip really does give it an edge over the standard Spectrum beeper, so that fireworks ending absolutely would've hit harder with proper sound.

And yeah, Spectrum compatibility was always a bit of a gray area on the 2068—very possible this was a port or at least heavily adapted. Keyboard play makes total sense too; that's how a lot of us tackled these back then.

That level 5 barrier lining up with the end of the game matches what we're seeing, so your memory's right on target. And agreed on the scrolling: for Z80-era hardware, especially with block memory moves being so slow, it's genuinely impressive. You can tell the programmer knew a few clever tricks to squeeze out performance.

Thanks for sharing, John. This is exactly the kind of firsthand detail that brings these games to life.


@john2001plus
14 hours ago (edited)
@chr@c @chronologicallygaming  I had a lot of Z80 programming experience.  I got to do it again on the Gameboy Color. It is a little easier to program than the 6502, because it has more registers and instructions. However, the 6502 is about twice as fast per clock cycle.  It was designed to be cheap and fast.



@john2001plus
3 hours ago (edited)
 @chronologicallygaming  The 16K video memory on the 2068 and Spectrum is contested memory, which means that the display chip has priority.  If you try to access the video memory while the display is being generated, then the processor will freeze until the horizontal or vertical blanking period.  

It is possible to swap memory banks in such a way that the vertical blank interrupt runs your code instead of ROM code.  This is a trick I didn't know back in the 1980s, but it would be useful for running all the video memory writes in the vertical blanking period, avoiding any processor halt.  (If most of the processor time is spent drawing to the screen anyway, such as my Diamond Mike game, then this trick might not help much.)

Unfortunately, BASIC code starts in the contested memory, which will affect the speed of BASIC programs.  I have read that there is a piece of ROM code that you can call which will relocate BASIC to the top 32K memory, which is uncontested memory.  This would make BASIC a little faster, but with less free space.  I wish that this had been the default, but that code in the ROM exists for a reason, so maybe they expected some people to use it.

The problem with the Block Memory Copy is that it does too many steps for every byte moved.  It moves a byte, increments two pointers, decrements a counter, and loops. This takes 21 clock cycles per byte.  However, if you knew that you were going to move a fixed number of bytes, such as 32 bytes on a line, you could write code that would move 32 bytes without looping.  Then you loop for each line you need to move.  

You could take this idea to a more extreme level, where you move 256 bytes without looping, but it would take 512 bytes of code.  However, the computer has kilobytes to spare.

If you need to write the same bytes to a block of  a memory, such as the clear screen command, you can temporarily hijack the Stack Pointer to do it faster.  This only takes 5.5 clock cycles per byte.  (I suspect that the BASIC clear screen command uses the slow block copy instruction, because it is not instantaneous.)

Mouse Trap (Intellivision)

Why Do We Say "Sprites"?

The word "Sprite" originally referred to fairies or spirits.  Within games, a sprite is a 2D object that can move independently from the background.   Your mouse cursor is a sprite.

It was obvious to me that "Space Invaders" did not have hardware sprites, because it moved the invaders one at a time instead of moving them all at once.  This led to a reportedly unintentional bug that became a feature;  as invaders were eliminated, the remaining invaders moved faster because there were fewer objects to move.

Two computers that I wrote games for in the 1980s did not have hardware sprites.  This puts the game at a disadvantage because the code has to draw objects to the screen, which is technically difficult and burdens the CPU.  This limits what an 8-bit computer without hardware sprites can do.  

I wrote software to emulate hardware sprites on the Atari ST.  Since it was a 16-bit computer, the extra computer power made this task easier.  Once computers and game systems reached 32-bit, they usually didn't bother to include hardware sprites because the processors were powerful enough to draw anything they wanted to the screen.

Deep Sea Adventure (CreatiVision)

Shark! Shark! (Intellivision)

E4M5: They Will Repent

@john2001plus
0 seconds ago
I was not liking this E4M5 map because of the apparent complexity.  There are areas that have layered mazes, where you have to drop down to explore lower paths.  This map seemed like a very confusing maze.

Part of the problem was with me; I tend to not study the map and just explore.  However, after I finally carefully studied the map, I understood the different rooms much better. The big room on the left was what confused me the most.  It has 5 entrances and 1 or 2 windows, making it look like a somewhat different room from each entrance.

There are only 2 secrets, which at first are hard to find, but once you learn where they are then the map is easy.  The keys are also easy to get, and you don't even need the yellow key to finish if you jump through a window to the exit.

I've changed my mind.  This is a brilliant map.  The complexity might put people off at first, but it is not near as hard as it looks.

Penetrator (ZX Spectrum)

@john2001plus7 minutes ago
7:41 I played a game that looked similar to this on the Timex-Sinclair 2068. The TS2068 isn't necessarily compatible with Spectrum games, but it could have been a port. I think the sound was better. If you did well, it gave you a fireworks show at the end.

Qix: Secret Strategy

https://www.youtube.com/watch?v=GUHoYanzPgg

Shark! Shark! (Intellivision)

The Complete Vector Arcade Journey

https://www.youtube.com/watch?v=swryO4xWOTk

E1M7: Computer Station

@john2001plus
After not playing Doom for at least a couple of decades, I have been alternating all the Doom and Doom II maps.  I am averaging about two maps per day.

Doom II is about twice as complicated and twice as hard as Doom.  Some maps take 45 minutes to get through.   By comparison, "Knee Deep in the Dead" seems pretty trivial to finish.  E1M7 might be the most complex map in the first episode, which makes it fun.

Because of the complexity and difficulty of Doom II, Doom feels like the better game, but Doom II has more replay value.  It takes longer to master.

The 4th episode of Doom, Thy Flesh Consumed, which was released as part of "Ultimate Doom" in 1995, is more complex and more difficult than the original Doom episodes.    The first three maps are very hard.  It has Doom II difficulty without being too complicated, so it is my favorite.

The Doom Clone Which Came FREE In Cereal Boxes (Chex Quest)