It should be compatible with every mod no matter how much it changes the player or enemy classes, and using a named script hopefully preventing
collisions with other mods.
I recently saw someone ask for how to extract Brutal Doom's AI marines, so decided to check them out. The code was a bit messy and hard to isolate,
so I wrote these from scratch using the same concept of teleporting by becoming an invisible, no-clipping actor, but using only vanilla resources and
modifying no classes. It's also much cleaner to look at and modify if you want.
This is mostly oriented to be used in single-player, so I am using current g/zdoom features without much regard for Zandronum
(you can get actual people instead, so no need for this). The marines behave like a drunk player would, but it's fun to carry in maps that
aren't Zandronum-compatible or just not possible to coop into them. They make for nice Invasion-style map (the few that exist out of Zandronum) companions.
The marine's power will be dependent on the amount of things in the map. This is a rough approximation, but you should get only marines up to lv.3
in regular Doom2 maps. But you will get lv.4 and lv.5 marines in slaughtermaps or monstrosities like Happy Time Circus 2.
To get your automatically-determined marine, type "summon aimarine" in your console. If you wish to have it spawn automatically, you can set the cvar
"aihelper_autospawn" to true. This is not default so it doesn't invade titlemaps like in Reelism. You can set the variable before starting the game and it'll autospawn from map01 onwards.
The helper is fairly strong and durable, and if killed it will respawn after about 30 seconds (double if xdeath), and they can use vanilla doom2 weapons.
You can override the automatic choice and spawn one of those with the code in parentheses.
Level 1 (summon doommarinel1_ai) will have a pistol and shotgun, no armor, low HP and speed.
Level 2 (summon doommarinel2_ai) will have pistol, shotgun and chaingun, green armor, a bit more HP and Speed, you'll see this guy the most in simple maps or beginning maps.
Level 3 (summon doommarinel3_ai) will have pistol, shotgun, chaingun and super shotgun. Blue armor, player-like HP and speed. You'll see this guy in later maps.
Level 4 (summon doommarinel4_ai) is mostly identical to lv.3, but adds plasma to his arsenal.
Level 5 (summon doommarinel5_ai) has the same weapons as lv.4, but has stronger armor.
The mod will become something else eventually, but wanted to make a release while it's still simple and using no resources or more complicated mechanics, so it's easier to autoload and forget about it, if desired.
Credit to the Brutal Doom devs for the concept and the "A_Recoil(-1)" trick. Everything else was written from scratch.
So far successfully tested with~
* DoomRL Arsenal and monster pack. No misbehavior whatsoever.
* Reelism. During debug they infiltrated the title screen.
* Brutal Doom. What inspired me to make these. Unlike the native ones, these live a vanilla life without fatalities and exploding into gibs.
* HAPPY TIME CIRCUS 2. It's surprising they can keep up. They seem to orient themselves better than myself in there.
* Psychic
* Wrath of Cronos. (won't scale as much as the player in power and there are summons so it's pointless to use...but if it works there, should work anywhere)
Known bugs:
* At times it'll teleport a bit too often, depends on level layout.
* It might get stuck once in a while after teleporting. Frag him or try to make it teleport again to fix.
* It might teleport inside the player. Punching it outside seems to be enough of a fix, but hasn't happened in a while.
* Using the "resurrect" command will pit them against you (fix: "give playertoken" in console). I consider this a feature though, as I would also shoot the undead guy suddenly coming back to life...
Updates:
1.0 "Vanilla" BETA 2
* Rewrote some of their logic to enable multiple marines at once, they will all stand still near the player instead of bouncing like inside a pinball.
* Rewrote their movement and targeting logic so they prioritize following the player over spreading hot lead.
* Made sure to remove a possible infinite loop.
* Improved the teleport beacon so it's faster, more precise and acts overall differently. The marines should reach the player much faster now.

I didn't have something better for screenshots since they look like plain, old, boring doomguys, but the screenshot kinda shows it works in TCs without issue.
Please use the attached pk3 while I don't have a more official link. But since it's small enough...