I will also add that only one Servant can feasibly kill Saver due to his God Hand-lite, discounting Ruler just Command Sealing him to death.

And that Servant is True Assassin post cannibalizing several families. (and Gil, but that's pretty obvious)

Odysseus and Tamulu [i]might[/i] be able to take him out, depending on if they can summon anything over B-Rank in damage. And even so, I'm sure A++ Strength is enough to take out anything they summon.

Killing the Master isn't an option due to that absurdly high IA, but it does reduce that END bonus from GK and actually makes it so the three guys up there can actually [i]do[/i] something about Saver.

TL;DR:
Should've made Assassin Hercules.