Ok, so about the health drain mechanic.
"Geometrical 1" doesn't feature a scripted drain mechanic as such.
It just uses a bunch of damaging sectors placed across the whole level.
That explains why things like door, decorations and areas where monster spawned don't make any damage, can't place two things on the same square.
Also, damage floor sectors can't be configured at all, so it makes random(3,9) damage each second at random.
Now, that being said, "Geometrical 2" actually features a more robust drain mechanic, it no longer uses damage sectors, it makes 1-2 dmg each 2 seconds and it only works on nightmare skill, so both the challenge and the mechanic is now worthy and more achievable.
So, in order to activate the script, I place a decoration at the very beggining of a room, to force the players to interact with said decoration before proceeding to the whole level.
That decoration becomes an unkillable monster that does hitscan damage, hitscan goes through walls, so that assures you constant damage regardless of where you are.
And since it's a monster, I can actually adjust both damage frequency and amount.
The engine has a randomizer of sorts, so never expect an accurate value.
So, it is doable via engine exploits, but it's quite hard to nail.
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Thankyou for you explanation and was my first guess logic wise of an invisible monster doing damage in a room but to learn in life learn to ask now that you have explained it ,i can still use the idea to exploit even more,you source code was very helpful to learn more.will try to test what you have said and looking forward to the new updates in the new engine
Yeah, I guess I should mention that the unused drain code I released on geo1 is not being used on geo2 and it was remade from scratch, as it's mostly a "monster" type of code. (Hacking a monster behaviour to loop damage after 2 seconds on death sequence. I haven't released the full version of geo2, so the code for it is not released yet, but I plan to do so, after the full version is released, just like i've did with geo1.)
(You can hear a low-pitched voice looping in the background while playing. hitscan has random chances of missing the shot, but still adds to the pressure, as hp drops gives you less points than the first counterpart.)