"I have a better opinion of you now, Rin. For you to kill Berserker even once.
But it's too bad. Berserker won't disappear just from that, because he has a body that won't die unless he's killed twelve times."
[...]
12 lives (11 resurrections) -> killed 6 times by Archer -> 6 lives (5 resurrections) -> killed 1 time by Rin -> 5 lives (4 resurrections)