With his burning sword and raging mana, the three giants quickly noticed him. However, none of them was happy about his return. Kahglia acknowledged that his Fireball had been powerful, but she could sense that Toz wasn't at such a high level. So, if he joined the fight, it was likely that he would get in the way rather than help her fight against the two undead giants.
And the undead giants were naturally pissed at Toz due to how he had tricked them into tanking the Fireball head-on. It was their fault since they were careless, but it was Toz's Fireball, so they blamed it all on him. And as soon as Toz stepped close, the Death Knight went after him while the Flesh Golem tried to hold on to Kahglia and force her to fight it instead of helping Toz or stopping the Death Knight.