• only Serious difficulty is reviewed. I mean what the point of playing that game on anything but Serious difficulty anyway?
  
• I don't care about Bright Islands
  
• overall, AlligatorPit fixed lots of broken spawners in TFE and fixed most of them in TSE's second episode (Persepolis). still there are lots of broken stuff (especially in TSE)

the maximum possible number of kills per levels are:

Moon Mountains has x2 broken enemy spawners and both of them are located on the last island:
two Reptiloids are supposed to spawn at some point but it never happens because developers' set "count total: 2" to their spawners, but there is only one trigger for each spawner

it means that two spawners "hold" two reptiloids each (four in total) but being activated only once. spawners spawn one Reptiloid each and then stand still waiting for next trigger to spawn two more enemies but that trigger never happens

same thing as with Moon Mountains above. one spawner shall spawn two Harpies, but is triggered only once...
...and the same thing with Kami - set to spawn two, but triggered only once

let's start with something easy. as with two levels above - one Flying Gnaar never appears because one spawner is triggered only once while set to spawn two enemies separately

now the hardest part of that tricky level. in west side of final area player takes a Golden Sphinx statuette. by doing so player ends the level with "358/359 kills but 9/10 secrets" stats. by destroying the raising platform with statuette before it reached the top player can grab it faster (it count as a secret), however four extra enemies will not spawn, leaving player with "354/359 kills but 10/10 secrets" stats

in other words player shall choose between getting a secret with missing four kills, or miss a secret but get four extra enemies

there is, however, a good way to mitigate this. by performing a double-rocket jump (with a combination of grenade and rocket) player can get inside without triggering the raising of platform. get statuette this way to spawn four extra enemies and then destroy a platform while it stands still

in first open-area there are two spawners that supposed to spawn x10 Firecrackers each (x20 in total). the bad news is their trigger is never called by anything, so they are just a dead weight

in last area, near exit, there is spawner that should spawn x5 Kamis (one by one with a delay), but it doesn't have a template (it means no specific enemy is set for that spawner, it is just empty)

finally, Croteam Fans. count how many spawners in the tunnel, and count how many bigheads in total. x16 spawners in tunnel, but only x15 guys

it is because one spawner doesn't have a template (empty). probably just a copy-paste mistake

all those errors and mistakes are weird because in original game (2001-2002 classics) there was one more broken spawner - one Bomber never spawned because of empty template. but for SS:Revolution developers removed him. so... they removed one specific broken spawner, but left three others intact? why...?

in the Minigun area there are two spawners that has no triggers whatsoever. there is nothing in level that can spawn those two enemies

in Yard of Strange-looking Heads there is a spawner with no template. just a sloppy mistake, because the very similar spawner in opposite corner is set to spawn an Arachnoid

and one Kami with Cannon Balls is never teleported from a template room. he is just stuck here and runs for eternity. poor guy (and no, template room is FAR AWAY from player and cannot be hit by a Serious Bomb)

x4 Kleers never appear in first area because there is no template for them (empty)

x1 spawn near final door doesn't appear either because of the same issue

x5 Kamis near "Secret Watcher" are kind of oddball: instead of being triggered, their spawner is set to "destroyed". so whenever you enter that area - game cancels those five Kamis instead of spawning them

and the final eleventh broken kill is another Kami with Cannon Balls stuck in a template room (as in The City of the Gods). a bad copy-paste mistake

x4 Frogs do not spawn in first area after picking an armor shard because they have no template (kind of trend here, yeap?)

and x3 Frogs with Serious Power do not spawn from a template room (copy-paste mistake from The Citadel level)

to start with, originally that level had 31 broken kills. AlligatorPit managed to reduce it to 12 only (one broken trigger). I am not quite sure why did they fix everything BUT that one trigger

anyway, there is a spawner for x12 Harpies that is never triggered by anything

four enemies in various parts of level have no templates. on bridge, in Clock Tower, in Citadel. then, after Clock Tower there is a spawner that suppose to spawn x4 enemies, but it has no template either. so, x8 templateless enemies in total

now, in Werebull area you fight Frogs. there are two spawners, 12 Frogs each, per 6 in batch
spawner on right is called twice (so it it will spawn 6+6 Frogs), but spawner on left is called only once (so, 6 Frogs are not spawned)

now. if our math if correct we should have -14 enemies so far. how we managed to get -10 then? remember Blue Biomechs and Kamis you fight in small village? x4 Biomechs have "Count Total" set to "zero", while their "Count Group" is set to "one". because of that they DO NOT increment total kills, but count towards killed enemies. so, if level wouldn't have broken kills, then you could have finished the level with "419/415 kills"

remember Kamis with Cannons? well, one Kami is never spawned because of broken trigger. you can clearly see four Kamis from away, but they magically turned into three Kamis when get nearby you. two Cannons = two missed Kamis

one Demon and one Arachnoid are set to spawn near the gate, but their trigger is not called by anything (same with Arachnoid who appears in COOP only)

same thing in Ice Lake area - two Biomechs have uncalled trigger

plus four enemies in Lava Caves have no templates

and a grand finale. developers put whopping x17 Biomechs in a template room for some reasons. they are never teleported, never get called, never spawned. they just tank down your total kills

first, there is a Werebull is never triggered by anything

then, there are two spawners for four Cucurbito (eight in total). but their trigger is set to inactive (that is something new)

and there is also a templateless spawner in template room (shall be Harpy)

and finally in Pumpkin Field there is a cannon that noclips through the ground (why?). thankfully you can destroy it with Serious Bomb

if you want to thank me...

...then check my guide about fixing various game issues: launching, crashing, optimization, stuttering, gamepads, etc. the guide is huge, but the topic is broad to begin with
https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=1935376439