Excellent animation. Also nice use of the dithering effect for the fadeout.

However the size doesn't fit proportion wise. The inner details/swirls are too big to match ingame scale.
I think the anim needs to be scaled down to 20% size, so the gaseous swirls match ingame scaling. But given the size, even scaled down it should still look pretty big.

Or add lots more much smaller swirls and details to the smoke, so it fits ingame proportions. But i assume render duration raises exponentially with the needed raised subdetail level.

Maybe you can make it more frayed and less clean circular in shape.

With an irregular shape, you could let the game play multiple of these downscaled anims next to each other and the frayed border would make them all partially overlap and fit well together into one big smoke area.
This way the modder can decide how big he wants the overall effect, simply by adjusting the number of next ot each other spawned anims.