>>18404458HP Ice doesn't help you against Dragonite.
>252 SpA Mega Charizard Y Hidden Power Ice vs. 4 HP / 0 SpD Multiscale Dragonite: 154-182 (47.5 - 56.1%) -- 81.6% chance to 2HKOYou'd HAVE to catch DNite on the switch otherwise it will Dragon Dance and kill you.
>+1 252+ Atk Dragonite Outrage vs. 0 HP / 4 Def Mega Charizard Y: 403-475 (135.6 - 159.9%) -- guaranteed OHKOYes, it helps against Salamence and Garchomp. But Garchomp, who is far more common, outspeeds and KOs with Stone Edge. So again, you have to get him on the switch. That leaves you with Salamence.
That being said, Charizard's alternatives aren't THAT much better, but Focus Blast at least helps deal with Tyranitar, Heatran, and the occasional Houndoom.
In the end, it really depends on what is best for your team. If you want to at least touch Dragonite and Garchomp with prediction, while being able to handle Salamence, go HP Ice. If you don't want to be walled by Heatran, TTar, and (Mega)Houndoom, and have a way to dispel them entirely, go with Focus Blast.
Neither option is very good, though.
