Just have Ribbion equiped and you wont get petrified, If you have this much trouble beat chaq then you might wanna leave the via infinito cause on the next 20 levels it becomes a random fight (you can run from then) and if you think chaq is hard next up is (SPOILER)Trema who has 1,000,000 Hps and Paragon who has 200,000 Hps you fight them with no chance to heal in between battles and (SPOILER)Trema does Ultima Metor as well as some powerful physical attacks and hes VERY quick you have to have all people at Lv. 99 to beat him