Don't forgot that Thick Fat pokemon like Hariyama and Grumpig can eat its Fire Blast. If Moltres wants to get past them it'll need hidden power dark for grumpig and ariel ace for hariyama. Also, bulky waters like Walrein, Blastoise, and Mantine (who would use hp electric?) generally are at least decent at eating FB and then firing back with surf. The sunny day set however, is asking for a free turn for its counters even though it negates most waters. But whatever it does, it gets at least two good counters.