Charizard is combo food. Between slow speed, a large hitbox, heavyweight status and pretty fast falling speed, as well as Charizard's slow aerials (rock smash included), really Charizard's most reliable approach options are an aerial approach (which is easy to punish because Charizard's aerials have pretty hefty landing lag), or Flamethrower (which can only be used so often due to stale moves, limited range and endlag). That being said,
if you can somehow navigate past an endless barrage of lightning bolts, fireballs and books, and
if you can get a grab past his aerials, Charizard's dthrow combos and uthrow KO can catch Robin off guard. Overall, I'd say it's about 60:40 in
's favor. However, since we're on the Charizard boards, not the Robin ones, I can't just leave it at that. My advice against Charizard mains, learn to predict the opponent's patterns of when they use Arcfire, and punish those patterns. From a distance, try forcing
him to approach
you. Shield against Elthunder and Thoron, but
avoid Arcthunder.
Do not shield it, especially when he's close up and/or has a book in his hands! You may have damaging throw combos and a deadly kill throw, but Robin's grab game is equally dangerous, especially if you're caught in a projectile trap or shieldstun. At very low percents, you can jump out of dthrow, or maybe even rock smash. At mid to high percents,
DI away. It'll allow you to more easily escape checkmate, as well as bthrow kills. As for escaping checkmate, you have four options. Attack, Airdodge, rock smash, or jump. If you attack, it's 50/50, decided by whether or not they try to read an airdodge. If you airdodge, you may survive, unless they read the dodge. If you rock smash, you'll get hit, but they'll also get hit, unless they read it and fall to the ground to punish. If you jump, you'll get hit, unless he tries to read any other option. The odds are stacked against you, but it's far from impossible (I mean, we aren't Sheik). Sidenote, beware of ledgetrump bair.