Howdy. I added Rampant 0.17.8 to a game in progress (I have Behemoths). I left Rampant's setting untouched. The game has very little mods, none of which modify enemies (mostly util stuff like Picker and Squeak Through).

Two things are readily apparent--1) when the behemoth spitters stand to attack, the turn from green to grayish and back to green when they stop attacking or die and 2) the spitters use the old style purple ball projectile instead of the new acid glob graphics. (It's a shame not to have the better looking graphics, even if the effect is different.)

The shading thing is probably a bug.

If you want the new projectiles, they will not be blockable by walls.

The force old projectiles in Rampant mod settings uses the same style of unblockable projectiles as vanilla without the updated graphics because it proceeds the vanilla change by a chunk of time.

The shading should be fixed in 0.17.9.

I also added some of the graphics and effects from vanilla.