Squirtle : 45-55. Peach's favor.
A good squirtle can stay toe to toe with a good peach. They are basically dead even in everything except killing power. Squirtle has a real hard time killing in general. Do smart floats every now and then or else you'll constantly eat squirtles fair. Throw many turnips, space appropriately and always tech to make sure you don't get jab locked. At high percentages, one good fair or fsmash will more then likely be enough to stock squirtle.
Ivysaur: 40-60. Peach's favor.
Not as bad as everyone makes it seem. Ivysaur does best at Midrange. Basically if you can't hit her with your second Jab, quickly roll away. DON'T roll towards her as you put yourself at risk of rolling right into a fsmash or a badly timed bullet seed. Speaking of bullet seed, did you know that Bullet Seeds initial hitbox (a small quake like feature (or the leaves?)) will only function unless the opponent is firmly on the ground? (*Much like Charizards Dsmash.) DI towards him if you get hit by the initial hitbox to avoid the seeds. Some common bullet seed setups include: FFCancelled Nair to Bullet Seed, Spot dodge to Bullet seed, and if you have bad DI, dthrow to Bullet Seed.
Like GaW, If Ivysaurs back is turned at anytime, expect a bair.
Ivysaur does the worst at the edges of the stage (because of fear of getting gimped) just pressure her and knock her off. Throw a turnip to keep her off. Remember, Ivysaur will try to Razor Leaf you off the ledge in order to secure a tether.
Once your invincibility frames are up, with proper aerial spacing, Ivysaur will try a last ditch attempt to knock you off the ledge with vine whip. A sweet spotted vine whip will more then likely stage spike you causing you to lose a stock before Ivysaur does which in turn wins games. (I LOVE doing this btw lol.)
Charizard: 50-50. Equal
Rock Smash destroys everything you do. It even destroys MK's tornado. Charizard WILL use Rock Smash. There is no exception. Its priority and power (could do 44%+ in one move) will ensure its use. A Charizards bair, fair (and IIRC nair, and uair) can all be short hopped with no landing lag and thus a Rock Smash will often be waiting for you at the end of these moves. Approach with care. You will more then likely die at stupidly low percentages if you get hit by his head during Rock Smash, so don't get hit. Rock smash weakness is it's bad ending lag so try to punish it frequently.
His usmash is also very good. It's speed and relatively far range of the first hitbox makes it great for follow ups especially after a Rock Smash. It's possible to DI out of his usmash by smash DI'ing towards him after the first hit.
He has melee marth's grab range so expect lots of shield grabbing. His Dthrow can kill (only at mid to high percentages though.)
Most of charizards good moves have noticeable ending lag, so punish away!..carefully (I.E. watch for sudden rocks lol.) Charizard has very little recovery options. Seriously, the best he can do is to either glide or rock smash on the way down. Take immediate advantage of this weakness and edgeguard the living daylight out of him. Overall Charizard hates pressure and doesn't like to be punished. His size doesn't help mich either.
Another thing about Charizard is that his fair has melee sheiks knockback (IMO). Only the initial hit within the wings and one of the ending hits will cause the knockback. All other hits in between has no priority and will cause little to no hit stun.
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Overall I give the matchup as a whole a 55-45. Peach's favor. Basically Squirtle will be used to try to counter your aerial game, Ivysaur for getting you at long range with razor leaf and midrange. And Charizard for killing you and grabbing you at close range.
