I have always been a had an interest in animals and monsters in sci-fi settings and fallout in no exception. So I want to hear your thoughts on what critters we may see, possible returning one or ideas for new creatures.

Well there's going to be some returning critters like the Super Mutants in their various forms, looking forward to tangling with the Behemoths again. The Yao-guai is back. It seems the molerats have had a bit of an overhaul but they are back too. Ghouls are in but I'm not sure if they are going to be having as many variants as they've had in the past. Radscorpions, Deathclaws are back but I'm not sure of Bloat Flies, Night Stalkers or other various insects like the giant ants.

Some newer critters that I've seen are the big Misquitos, the Androids but I haven't seen a lot of other new stuff.

I can't wait to see how the fauna acts in F4! Im really hoping that in addition to the predators like Yao Guai and Deathclaws, we also get some more peaceful creatures like mutated deer and maybe some of those squirels and iguanas folks like to put on sticks so well.

Concept art shows: 2 headed deer/elk of some kind. Points to whoever names it properly. Also per the Concept art/Special videos it looks like the Queen Molerat may have made it in. Also looks to be some kind of giant mirelurk queen from game footage, the giant mosquito, radscorps, and it looked like bloat flies made it back into the concept art.

I am a bit surprised that we have not had any indicator of giant ants of any kind. really enjoyed the unscripted ant war in fallout 3 even if the zone was buggy as hell.

Edit: Come to think of it even if ants didn't make it the list is a vast improvement from F3. The game world is only so big and you would have to squeek in raiders and super mutants somewhere.

I hope they reintroduce some of the creepier monsters from Fallout 1, like the floaters, and two-headed centaurs.

http://fallout.wikia.com/wiki/Floater

Cazadores I could do without, because ouch.

Ooohh floaters would be nice. I like the way you think.

appeared a queen ant in the last video of the s.p.e.c.i.a.l

They are quite unlikely to return. They were created by the Think Tank and are likely limited to Mojave and nearby areas. For them to appear in Commonwealth would not make sense lorewise.

They were to appear in fallout 3 but were cut.

New creature both hostile and especially passive would be a plus Imo, I'd also like to see some new variants on the older enemies. I saw in the combat montage a siege breaker sentry bot that had heavier armor and weaponry. But more.variation to other enemies would be great too, like a dwarfed death claw with more speed but none of the armored body of it's larger cousins or bloatflies that have glowing abdomens that blind you with a bright flash of light if your too close.

I'd like to see a predator-prey system were some animals will attack each other instead of you, for example I remember seeing a mutant bat in the concept art. I can see them attacking bloodbugs and bloatflies if their in close proximity.

I'm wondering if we'll get creature variants, though, like difference textures and patterns and sizes. I had to mod that into the game in Skyrim so not every single critter looked precisely the same, and it was annoying to mod.