Wall Crabs are really annoying (edit: but I prefer them to Clockwork Pigeons). Thankfully, they do very little damage. Hungry Ghosts more or less keep me out of The Deep, for now. Feral Chickens are in Forests. I don't think I've seen very many Lava Flats enemies either--you just don't have to go through the Lava flats to beat the game, as there is only one Level-up Windmill behind them. Merc coins and Amp Towers can keep you from encountering an entire biome of enemies, if used right. I haven't seen most of the enemies in The Deep, and I've only seen a few enemies from the Lava Flats.
I do think that the lava flats as well as the Deep could be made to have a bit more of a presence in the game. There's just not enough of either on the world map (but there IS a TON of ice/snow areas....). It really is possible to completely ignore either, if you do it right. Particularly with the lava flats; eventually you do have to enter them (unlike the Deep), but as it's sort of a late-game area, chances are you have a pile of coins by then....
The enemies in the Deep though arent quite as bad as I'd originally thought; the unkillable ghost things, along with the extremely high danger level of that type of tile, tend to give the impression that it's ridiculously hard, but.... yeah, not as bad as I'd thought. Though it's definitely geared towards being more of a late game area, waiting until the final tier of spells isnt absolutely necessary to go in there, but it IS a very good idea. I actually thought the Lava Flats were a bit harder than the Deep, particularly considering the lava, and that certain enemies violently explode when beaten.
I think they're both neat areas, so it's a shame that they just arent seen much.
As for the chickens.... there do seem to be a few enemies in the game that could be classified as "very rare", and that's one of them. I've seen them, but only a few (and they're rather dangerous, actually.... horribly fast little jerks). And heck, some things seem even more rare.... there were 2 types of robotic enemies that I'd never even once seen until one very specific room when I was playing it yesterday (both are really nasty floating types that drop stuff downwards). Saw them in that one single room, aint seen them since, hadnt seen them before. Or those spinning green blob things, I've run into maybe TWO of those in my current game, and that's it.
