DreadLord Death Reversed

[maracujah]

Hi, I wanted to make this summoning spell, in which the summoned unit is a Dreadlord, and I wanted to have the effect of the dreadlord being summoned, like the Infernal has this effect of the falling rock. Only in this case, the "effect" would be the dreadlord death animation backwards, I mean, as if many bats were gathering, and then the Dreadlord comes out of the air, spinning and everything.

I have tried doing it myself, and I researched, but still I failed.

Thanks in advance.