"forgotten beasts" like enemies

[konlexa]

pros
-makes each game unique. Because fighting "giant one-eyed cricket" or "huge hairy slug with wings" - is a thing to remember
-could solve "killbox" problem. Your killbox wont save you from enemies that can jump over/fly over/dig under/climb over/teleport/move through walls
-makes endgame harder,maybe A LOT HARDER. most of endgame raids just a new human leather hat resource
-lore friendly Science can go too far experimenting with genes.Especially in far future,where space travel and Glitterworlds exists.Combining Thrumbo,Megaspider and Warg,what can possably go wrong?Or maybe building enormous plasteel mechanoid.
-using of rare damage types Beasts with flamethrower or build-in mortar,with toxic bite and capable of driving crazy with its "mind" would force players to learn how to treat such damage types
P.S.: "what are these "forgotten beasts"" -
  http://dwarffortresswiki.org/index.php/DF2014:Forgotten_beast

[SirDerpface]

Cons: Probably impossible to make.

[Lowkey1987]

Perhaps you could the ship-parts as a body which afflict things arround it. Like a tank, which can emite a forcefield against mortas (which can kill any raid in the endgame) and also can sometimes shoot mortas on short range.

We dont need BIG things, but something, a modder could use