Well, highest yet would be 170 in Lhusu Mines from Skellitons.

But the HARDEST Chain was a 70-75 chain By doing Werewolfs in Giza plains. The hard parts was going to and fro from 2 screens (North, getting mobbed by Urstirx and wolfs and the like) And the werewolfs, Thier lvl ranges from 19 to 22!