@Saladking: that's hulk at his strongest. it takes quite some time for hulk to reach that power
Hulk had that power all along but he kept it bottled up until he was given the opportunity to let loose knowing he could use his last wish to bring everyone back and the fact that he wasn't in his home dimension anymore. Hulk actually does care about the earth so even when "bloodlusted" he's still subconsciously holding back so I never understood why people think WBH is hard for him to trigger. He can go WBH whenever he wants.