So me and my friend are playing a game of phyrexians vs eldrazi, you know invaders vs invaders, and he brings out spellskite, next turn (I have ulamog out) I play emrakrul, as attack with ulamog, he says in response he uses spellskite to take ulamogs anhialator, and emrakrul a anhialator and both teir indestructible and flying, can that be done?
{Spellskite}
In short, no.
To elaborate, {Spellskite} does not take abilities or spells; it changes their targets to itself.
To further elaborate, {Spellskite} can only change something that targets. Annhilator does not target. The only thing he can do that involves Spellskite and annhilator is sac it :p