.frame specifies the framegroup
.frametime specifies the time into the framegroup.
this results in a 4-way blend between the two frames of the new framegroup and the two frames of the old framegroup.
if you then send the time at which the animation was meant to start from the server, and calc the frametime as time - startime, then someone seeing a death half way through or after the event will see it starting half way through or already dead.
how you encode the time can vary. one way is as 'X seconds ago' rather than the absolute time, as this can be sent in a single byte. You'll want to scale it.