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ya i was curious abou that for the creatures with no models. i was just hoping gw would come out with them in the future.
I'll use the regular round bases for the time being.
"I have seen you humans, trying to forge an Empire in the name of a corpse"
I'd say use the standard MC base as long as your end result isn't too big. My forgeworld trygon is on an even bigger base, but that's to be expected since the lower part of it is larger than the MC base itself.
tervigon by it's picture in the codex could definitely be a carnifex base. Tyrannofexes are terrible so don't use one in an actual game but for modelling purposes a trygon base might be best. And valkyrie base is perfect for harpy
WH 40k Armies (W/L/D):
Tyranid: 2250 Points of Awesome (5/4/1)
Necrons: 1000 Points (4/0/1)