Annoyance because you're dead, or....?

Space marines, who follows a fake god that is dying, they need to be corrected.

For me the most fun would be the squishy human things with the shall of metal its kinda cranchy when you bite into it. and I hear there bones make good armor

For me it would be Spess Mon'Keighs in all of their variations and colors. They will get the answer to the question of superiority on the tip of my blade.
And the servants of She Who Thirsts, of course. They deserve a quick death, as there are so many to kill)

Will most probably prefer killing nids as a Space Marine.

As an Ork though, I'd kill kay-oss marines more.

There's just something satisfying about killing Orks.

da one what puts up da best fight.

Xenos!

Ultramarines and squishy little Eldar.

Nothing will make me more happy than killing eldar scum