Charizard is good in lag... in theory. He hits hard, he has that lovely flamethrower, and I won't lie. Flamethrower is
amazing in and out of lag. It's just a good move period. The downside is that flamethrower is the sole reason why charizard doesn't get pooped on in the neutral by most characters. His moves are fairly slow, have tons of cooldown, and are easily punished even in lag. If your chararacter has a solid way to get around flamethrower, charizard will have a tough time.
(Examples: Rob's Lazer goes thorugh it. ZSS can flip kick charizard for commiting to it on reaction. Yoshi's outrange and pierce through it)
I suggest you head over to the charizard boards and look at the metagame discussion. See what the #1 weakness people complain about it. I guarantee you it will be that his neutral is bad. I said before that charizard's approach game is bad. He can't just rush people down without some kind of gameplan. He doesn't have the safest of pokes to toss out in the neutral. He needs a soft read at least in order to land a hit. The only safe thing he can do in neutral against most characters is flamethrower. It's an amazing move, but does not make up for his lack of a neutral game over all. He cannot spam it either. It's a one time use move, then he has to do without it for a while. If the enemy avoids it, he's in lag for long enough to punish him before he can move out of the way.
Rocksmash is good, but has a ton of cooldown. Rocksmash helps make char's anti-approach game good enough that you can't just rush him down blindly, but if you can bait this move out, it's a free punish for you. Fast characters excel at this. Campy charaters only have to worry about rocksmash at close rage. It's mostly a "get off me tool", and a risky one at that.
Flarebltiz isn't good in lag. I can say from experience that it is not, that is a
very common misconception about char. Flareblitz isn't good in lag because the opponent has plenty of time to react to it. It has an extremely obvious visual and audio que before it goes off. If you look out for that and press shield the instant you see/hear it, you're fine. Not only that, you get a free punish on charizard... and getting punished as charizard is terrible. It's so easy to wrack up % on him once you've got him in the air.
Flareblitz can be hard to dodge, but only under three circumstances.
1. The enemy is trying to land without their double jump.
Flareblitz is amazing for punishing landings. If the enemy has no double jump, and you time it properly they won't be able to avoid it.
The thing is, lag actually makes this
harder to do. You have to time it perfectly, or the enemy will land and shield. If that happens. RIP
2. After a missed Tech.
Flare Blitz is great for tech chasing, It covers multiple options at once. But once again, lag actually makes this harder to do, since miss-timing the flare blitz will often send you off stage. Once that happens it's good bye stage control.
3. If the opponent has already commited to something
This is a read. If you know for a fact that the enemy is going to commit to something laggy, like a projectile, blitz will armor though it and hit them.
But there's a pattern to all of this, all of these things need to be timed well in order to work. If you do it just a split second too late, good opponents
will shield and punish.
As for the rest of his moves. They're all fairly slow with mediocre priority at best. He's not a difficult character to react to if he's rushing at you. His combos are read-reliant, he has to be on point with his reads or the enemy can often just toss out an attack and outspeed or outprioritize his.
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