User blog comment:Pokemon Trainer Lion/Pokemon Battle Royale-MEGA REMATCH/@comment-26030372-20160225153827/@comment-26030372-20160303184119

Don't know if Venusaur could really hurt Charizard... honestly even with Thick Fat the lizard's just too fast and even if I removed Fire Blast there's still Air Slash and Wing Attack... even then two Flare Blitzes are doomsday for Venusaur and Worry Seed, while removing Tough Claws, would still leave hellishly dangerous Air Slashes.

Last of all, as hot as SolarBeam is, it's only 30 base power when used against Fire/Dragon Mega Charizard. Besides that, Venusaur wouldn't survive too much and even with Leech Seed Charizard would still lay waste to him with attacks like Air Slash and Flare Blitz. Even with bulk, a STAB Tough Claws Flare Blitz, even when normal effective, is no everyday punch to the stomach.

And even without Tough Claws, we still have the cannon due to Special Attack. There's also Heat Wave, Inferno and Flamethrower, and Venusaur's got NOTHING, save Double Edge to hurt Zard.

So yeah, Charizard does win.