Marticar is a level 63 rare mob Spore Walker. He is faster than the average mob, and also has a lot of more health than them. He is immune to fear, slow, and immbolization effects. He hits for 900 on cloth wearers (with mitigation) and has an nature based attack which pulls a single player toward Marticar, himself.
Marticar is a criteria of the achievements:
Patch 2.4.0 (25-Mar-2008): The following creatures have had their hit points and damage significantly reduced: Collidus the Warp-Watcher, Fulgorge, Hemathion, Kraator, Marticar, Morcrush, and Nuramoc