How did they do that?? Batman Doom (SPOILERS)

[Illdo]

Do you know how was some tricks in Batman Doom made??
Like: moving train (I know how to give an illusion of moving, but I don't know how did they change the station's looks?)
Killer Croc which throws rocks
Mayor Kroll which dies after a certain time
Big explosion wall in Axis Chemicals
Waving flag!
...and more

[Scuba Steve]

Moving Train: The train never moves, but as you cross lines in the train it raises and lowers sectors in the train station and when you leave gives the appearance it has changed.

Killer Croc: Killer Croc is an Arch Vile and the rocks are dead corpses. When he goes to resurrect the rocks, he changes to an attack frame.

Mayor Kroll: Probably just has a long time delay on a frame before going to his death frame where he explodes and triggers the end level flag when dead.

Axis Chemical: This is probably one of the most impressive things in Batman Doom. I would imagine something like a projectile is fired at you that summons the effect of the end of map 30 in Doom 2, and as it travels it continually fires wall explosions. I'm not positive how this one is done.

Waving Flag: The flag is an animated texture it's really complicated that certain segments are blanks while others are visible as the flag "waves" to that section. Check it out in a map editor, it explains it much better than I can.

Batman Doom is amazing, especially since it is all done using Doom2.exe. Some other impressive or unique feats are multiple uses of tag 666 in the Arkham Assylum, Filling the Hospital with gas, and your final fight with bane using only your fists.

[Illdo]

Moving Train: The train never moves, but as you cross lines in the train it raises and lowers sectors in the train station and when you leave gives the appearance it has changed.

How did they made the traffic cones to appear?

Filling the Hospital with gas
It really can fill with gas?? I always though it was just a bluff.

[Scuba Steve]

Since it is Doom.exe compatible, there are no boom conveyor belts (or Doomsday lol). The way The creators figured out how to spawn static objects was to place destroyable objects 1 pixel from a teleporting line. A silent rocket hears you on the train and explodes, killing them and turning them into their death frame (a traffic cone) while pushing them across the teleporting line where they appear at the destination.

The Room filling with gas is a trick that has been done before, most noteably in Dystopia 3. A dummy of you sits in a room with a very high ceiling that takes approx. 4 minutes to lower. When the ceiling lowers it crushes the dummy you and thus "Gasses" you. If you try to play Batman Doom with Legacy you may not have ever been gassed because Legacy removed the voodoo dolls.