well it all depends on how many minions you got, how many of those are caster minions (use magic), and how long it takes you to kill meph. meph summons skeleton magi, which cause alot of lag by themselves (if you do uber xp runs you know what i mean). Ive only had one game crash on me when using a summonmancer, but i had a grand total of 24 skeleton warriors, 18 Magi, and 42 revives, 1 golem, a grizzly and my merc. when I teled on meph my FPS went from 126 down to 2, and I got crashed out. It's only happened once, and i was experimenting on if I could keep my full army up. For future runs I dropped the number of minions and never crashed again.