009CEC90: Horizontal speed of Kirby (type: float).
009D1F50: Vertical speed of Kirby (type: float).
00A1A3EC: Horizontal position value of Kirby (type: float).
00A1A3F0: Vertical position value of Kirby (type: float).

Click here to download all the memory adresses. Thanks to Anavrin for finding these addresses.

Horizontal movement

From slowest to fastest in general:

• Walking top speed: 5
  • Walking upward does not slow you down.

• Running top speed: 6
  • Get in running speed as often as possible.

• Rock bird flying top speed: 6
  • You need rock + cutter to get into the rock bird form.

• Slide kick top speed: 9
  • Try to slide kick off ledges when possible.

• Curling top speed: 9.7
  • Speed decreases over time so do not stay in this form for too long.

• Double fire top speed: 10

• Single fire top speed: 10.5
  • Doing an air-puff after each fire blow keeps your speed for a bit more distance.

Vertical movement

Upward:

• Initial upward speed from jump: ~16
  • Walking upward and jumping does not reduce initial jump speed.

• Flying upward speed: 4~7
  • The fastest way to fly upward is to rapidly tap the "A" button.

Downward:

• Terminal downward speed: -16
  • To save time falling down a pit or shaft, jump ahead of time and just barely miss the edge of the hole. The result is that Kirby pre-accelerates himself into the hole and starts his descent with more than zero downward speed. Have as much velocity as possible before dropping down:

• Try to slidekick before entering a new room or map. You should slidekick ~26 frames before seeing Kirby's running animation into the room.

• All of Kirby's moves are slown down in water. Try to swallow enemies and use power-ups outside of water as often as possible.

• Swimming with a fish over your head saves time.

• Many times in this game, you'll need to get rid of power-ups. The common way of doing so is to press the "R" button to pull-off the power-up on your head and then you can throw it at enemies or in the air. Though, it is faster to make enemies hit the power-up you pulled on your head instead of throwing it.

• There is also times where you need to pull-off the power up on your head to swing it at other enemies to create a new power-up (double fire, for example). In those cases, this trick can come handy:

To do this trick, you need to press "R" or any "C" button on the last possible frame before entering a room or map. Instead of pulling-off the power-up on his head, Kirby will get the power-up back in his mouth, which can't be done without this trick.