Give me some advice guys:
1) First off I know I F-air too much. It's partly because I used to play Luigi a lot but also some of those are supposed to be N-airs.
2) I don't really know how to use pills...I just throw them out and hope they mess up the other guy somewhat
3) These are all friendlies
Vs. Marth
http://www.youtube.com/watch?v=bCIK8nLiXvY
Comments - This Marth hasn't been playing all that long
Vs. Peach
http://www.youtube.com/watch?v=0wsxhugfUPk&feature=channel_page
Comments - Fighting Peach on FD is annoying...I mean what do I do if they float just above pill-bouncing heights? I also realize I shouldn't try to ledgehop F-air.
Vs. Falcon
http://www.youtube.com/watch?v=IaiDwQgDEtM
Comments - Falcon's hard
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Is there anyway to DI out of D-throw -> knee?
I watched the first one. I can't give you advice on it, because the marth needs a lot of work. If the marth knew how to CC, you would probably get *****, no offence.
The only thing I can tell you, is to use more u-air when he's above you and don't approach him from above.
I'll periodically edit the post and add stuff as I'm watching the other 2.
edit: you should cape peach's turnips and also use d-smash offensively more. Don't n-air peach when she's on the ground, otherwise you will get CC -> d-smashed by her. B-air is better offensively when they're on the ground because if they CC, it will knock them too far away to hit you with an attack.
If peach is too high to get hit by pills, use u-air coming from below. If you catch her with bad DI, then follow up. If she has good DI, then wait on the ground for her to try to attack you, then counter-attack with either u-tilt / u-smash / d-smash.
You can also use u-smash for kills when she is around 100%, when she is in the air. He is invincible on his head during the attack, so it will beat almost all of her moves when she's above you. If she's above you at a fairly low height, just use u-tilt. It will either launch her, or knock her away.
Edit2: You neglect one of the most important things with doc: YOU NEVER GRAB!! d-throw / up-throw -> free move (and maybe 2 or 3 more) is awesome for doc. You need to take advantage of when they are vaunerable with grabs. For example: when they are shielding in front of you, or teching, or side-stepping, you can wait and grab them.
Edit3: There is no way out of d-throw -> knee over 65%, if falcon does it properly. Not a lot of falcon players can do it though, so DI away and bank on them screwing up.
Also vs Falcon, use u-tilt / u-smash to stop his approaches (unless it's a knee coming at you).
Also, try Wavedashing out of shield to escape pressure, especially if they use a laggy attack.
Edgeguarding vs falcon, use b-air so that he won't be able to recover high. Then you can edgehog, or cape him when he's low enough.