Maggoc has a stacking healing debuff (5% healing reduction every 15 seconds or so) and throws boulders which daze at random targets. The debuff appears to be a normal melee attack, and can miss; a high-mitigation tank that can dodge/parry at a high rate can keep it from stacking. He hits a well geared druid for about 600, so a warrior should expect hits between 900 and 1000. Maggoc will also occasionally enrage for 10-15 seconds, substantially increasing his damage output.