If I missed anything or made any mistakes, please tell me. If you have a better or clearer description for a sweetspot, also tell me. This stuff is pretty obvious, but it's a nice resource.

Use ctrl+F and type in your character's name to find their list of meteors. Some characters do not have meteors.

In case you didn't know:

Spike- An attack that sends theopponent directly downwards until hitstun wears off and cannot be canceled. These do not exist in Brawl - explained below.

Meteor Smash- An attack that sends theopponent directly downwards until hitstun wears off or until it has been meteor-canceled.

Stall-then-fall - An attack that sends the user directly downwards until hitlag wears off. Some stall-then-falls are spikes if they hit as the user begins their downward movement (i.e. Game and Watch or Toon Link)

Semi-spike - An attack that sends the opponent horizontally, with significant downward momentum. Semi-spikes are not technically meteors, and cannot be meteor-canceled.

Footstool Jump - Performed by pressing jump while a short distance above your opponent, if done in the air, a Footstool Jump acts as a weak spike. Its best use is to space aerials, like Marth's or Toon Link's Dair.

Meteor-canceling

Meteor-canceling, while still present in Brawl, is performed slightly differently. In Melee, if the player uses a second or third jump immediately after being meteored, the effects of the meteor smash will cancel, and the player is given the opportunity to recover. The higher your damage, the more difficult meteor-canceling becomes, as you fly downwards at a faster rate.

The key difference to meteor-canceling in Brawl is the time at which you input your second or third jump. Much like teching, if you press X or Y too early you will be unable to meteor cancel again for a set number of frames. Rather than jumping immediately after being meteored, you must wait a set amount of time before canceling. A way to avoid this is by using your third jump (Up-B), rather than your second jump, to cancel. As Doval discovered, you can “mash Up-B as much as you like, and you’ll get a Meteor Cancel every time.” This technique works because the number of frames you must wait before meteor-canceling does not reset when you press UP on the control stick, only when you press X or Y. This works whether Tap Jump is set to on or off.

The amount of time you must wait before meteor-canceling is approximately half the time it takes for hitstun to naturally wear off your character. BE CAREFUL: In Melee, all characters could meteor-cancel with their jumps, but the same does not hold true in Brawl. Pit, and possibly other characters with multiple jumps, cannot meteor-cancel with his second jump or Up-B. Also of note is that it is possible to meteor-cancel with a tether that is not a third jump (i.e. Lucas’ grab).

At this point assume that all spikes are Meteor Smashes. Why? My theory is that spikes were unintentionally a part of Melee. There are only five true spikes in Melee. Captain Falcon’s D-air only spiked at the nipple, whereas it is a meteor everywhere else on the hitbox. Roy, who usually sweetspots at the center of his sword, spikes at the tip of his U-Smash. Marth’s D-air spike was removed from the PAL version of Melee, and replaced with a Meteor Smash. It is possible Melee spikes were only a result of developer oversight while coding the conditions for a Meteor Smash to be canceled.

Sakurai, and the HAL team, do not distinguish between spikes and meteors in either game. On the Smash Bros. DOJO, Sakurai does not indicate that there are any other techniques that send the opponent directly downward, that also behave differently than Meteor Smashes. While there have been many examples thus far of developer error in Brawl’s engine, it seems unlikely they would neglect to include meteor-canceling on all Meteor Smashes. This just means you’ll have to get used to the new meteor-cancel system. When you’re edgeguarding off the stage, at times it may be more advantageous to use a semi-spike, which cannot be meteor-canceled.