Yay, I've been thinking for a while who's the best fire Pokémon of them all and it's got to be one of these two. But, one on one, I can't come out with a definite winner. There are combinations in which one beats another (different items, attacks, EVs, nature), but of course there are also inverse combinations.

Mainly it revolves around two types of Charizard and two types of Ho-oh:

Charizard

with rock slide / rock tomb OR
with counter

Ho-oh

with ancient power / hidden power rock OR
with thunder

So... can you come up with some moveset for any of these 2, which always and invariably beats the other?