The biggun is the Spawn Mother from Malifaux. The blue ones are Tiik Warriors from Reaper. Don't recognise the other two.
Correct so far. I happened to have a list handy:
Reaper 03616 Tiik Warriors
Reaper 50168 Sea Creature of Blood Reef
Mage Knight 543 Deep Spawn
Wyrd WYR4054 Spawn Mother
Even though I've traditionally preferred frontal team shots with odd buildings in the background, I suddenly got this idea when I realised that most of these figures look more interesting from their side (possibly excluding the Mage Knight mini). Then it turned easily into a scene from a classical CoC adventure. There are even some non-Euclidean bits because this piece of cobblestone wallpaper is warped from painting...
I should play more games.