I've been killing those trolls for loot. With this guy, I use body slam and jump. (level 92 started around 84) With Blade Savage daggers and poisons (level 72, I started around level 50) - because I now have the jump timing down. The large part of it if your a low level caster - bring pots and a pet. Melee Heavy Armor - Body Slam - remember to move to the side or through him before he falls on you. Light like Blade Savage - Keep Dodge and Evasion up, poisons and fire. Above all - get your jump timing down and don't let him get far enough away top keep chucking boulders at you.