I'd like to see more intricate infighting. Like two monsters that just have an absolute hatred for each other, and will go after each other if they get a whiff of the other's smell or something. 

Q1's monsterset, even default, is probably the best ever. Out of the new abilities you mention, I'd say wall/ceiling climbing is by far the best, in that it really adds to the gameplay. Poison sucks (it was in CoE and dropped for SoE). Homing shots, ala Vores, I think has been exploited (by me - lol) too much - there should be a monster with homing shots that do much less damage but home faster. That way, it wouldn't be a linear "run away, find an obstacle" thing. I realize I did force the player to do this in nsoe3 and 4, but to me it seemed like Vores hadn't been used that way before and if you really wanted to, you could take them out (otherwise they were a constant source of tension).

Quoth additions are extremely well designed, especially the Gaunt. Quoth basically outdoes all other new monsters, in actually creating new monsters that the player must fight in a new way (although I think nsoe bane has quite a few tricks up his sleeve).

Overall, new monsters fall into two categories: those that change the gameplay (ie Quoth additions) and those who are basically "same old" but look different. Even now there are very likely new "styles" of monster that have yet to be implemented/exploited. 

soldiers who use cover, and retreat to more cover then blind-fire, or pop out from behind cover, take a few shots then hide again 

Travail's take on poisoning the player was fairly cool, it'd be great if people used them in their own projects more. If one would get poisoned, it was usually their own fault, rather than the unfair gameplay's.

As for the rest of ideas:
spawning/cloning - it's one painfully cliched method.

teleportation - overdone.

shields - I usually dislike shielded monsters (if the designer wants people to waste ammo on a monster, why not just give them more hit points?) but the Death Lord (Quoth) did it well.


An idea I recently had is making a monster damagable, but impervious to pain - basically it wouldn't go into pain frames unless seriously damaged. It would make the player have to act quickly before he finds himself cornered by a group of those. 

Will muse on it. 

Cover makes things so static. It reduces a game that's about movement and aiming and target priority and dodging and shooting to basically precision whackamole. Not really fun IMO. The way you usually deal with monsters who behave that way is to snipe them off or just go up to them and execute them in their hiding places, which also isn't much fun.

Quake really is better when the maps are interconnected and non-linear, because it makes you move around and mix it up and deal with monsters from all angles - czg03, dm3rmx, and gmsp3 are all awesome examples of this. Real linear maps don't work so well, because the player winds up in a pattern of "go forward 5% more, back up while you kill the stuff chasing you, go forward a little more than before." Face to face firing-squad cover gameplay is more suited to that kind of level design. 

it would increase realism?