Painkiller - Supernatural 2.0
Don't be deceived by "2.0" numeration because it's still neither polished nor finished. And most likely won't be - it's been years since its release.
me after playing this mod
Played that one to see if the maps from other Painkiller games (not released by original creators, but fans and modders) in more polished form. Turns out they were only a bit better than original (mostly by cutting down loading times, unless you save in certain spots which cause makes loading way longer for some reasons), but still with some shit ideas because modders gonna modders of course. Add that soviet sadomasochistic tendencies from STALKER mods and you can get the picture.
Speaking of STALKER there's power plant level with anomalies - both effects and sounds borrowed from GSC production.
Some requirements for tarot cards were quite brutal. No souls or ammo collected on 500+ mobs maps? Truly Pain and Killer...
Surprisingly one level that requires all secrets was easy, except one. Why?
Invisible walls.
If you check any gameplay videos with secrets hunting (or you've played the game yourself) you would see a lot of bunny hopping, jumping and hugging obstacles/walls to reach the higher points.
This modder was toxic and sadistic enough to put random invisible walls (or even "death zones" that nuke your character, forcing reload your save) making the hunt even more obnoxious. Bonus point for putting them near death zones like water or spikes or deadly heights. You won't see them, making the whole ordeal more confusing and obnoxious.
see this one? You could easily jump there even without bunny hopping, but some invisible wall is here and you just fall like a bitch.
Oh and this mod adds even more secrets to the levels.
First level from final chapter requires 3 shortcuts to be found. After wasting hours, in a level that should take at most 15min, I've realized way too late that you can't get that card without cheating. You have to either beat the level or get the shortcuts, which in turn get you stuck because scripts are breaking. With the powers of Powermad mod you activate noclip, get the shortcut, return to the previous position and continue.
this is the whole collection, no more levels to beat. Nice sorting btw.
No idea what Perfect Warrior gives, or random artifacts around the maps. No text or visual changes, nothing.
There's X-Files section avaiable with more maps, some of them bugged and unfinished. Those working are quite brutal, throwing a lot of accurate shooting enemies.
There are other PK mods (Reload, Lost Alpha, Fear Factor and others) but they are similar - some changes and sadistic difficulty level, especially secrets. Which explains why commercial Painkillers like Recurring Evil, Redemption and Resurrection (none of the made by original team People Can Fly) were garbage.
There are some things from Necrovision like vampiric rifles+magic gauntlet and some enemies.
Plus OP rifles from alpha/beta version of PK.
They share the engine, which makes assets porting easier. Similar case with Metro assets in STALKER mods even though it's not officialy confirmed that they share the code.