Vertical Speed

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Introduction

There are two memory addresses for vertical speed. The first can either have a value of 1 or 2, where 1 is for rising and 2 is for falling. The second is for the vertical speed, and is always used regardless of the first's value.

Values in the table are in hexadecimal, so 0.1 is equivalent to 1/16 of a pixel

"Ramp" means the number of frames the source takes to reach the amount listed in the column.

"HGBFS" stands for "height gained before falling starts."

Crouching before jumping will cause Samus to begin her jump eight pixels higher than if she did not crouch.

Moonfall is a glitch that underflows the fall speed, allowing you to continuously gain speed without hitting the cap. When doing a moonfall, the address used for direction has a value of 0.

The below give values in the various mediums of (air, water, lava/acid). For water and lava/acid, it should be assumed Samus does not have Gravity Suit equipped: With Gravity Suit, these mediums behave as air (for purposes of vertical speed).

Speed Values

Acceleration of Gravity

The acceleration of gravity is the amount that Samus's speed changes each frame, decreasing it if she is moving upward and increasing it when she is moving downward. There are some exceptions; for example, if she is at her fall speed cap (see next section), or when changing directions (where her speed is first zeroed). The values shown are in pixels per frame per frame and all assume that Samus does not have the Gravity Suit equipped

Region Medium Acceleration
NTSC Air 0.1C
NTSC Water 0.08
NTSC Lava/acid 0.9
PAL Air 0.28
PAL Water 0.0999
PAL Lava/acid 0.0ACC

Compared with Run Speed

Air Physics

Air jump velocity.png

Air jump height.png

The height shown is the height in which Samus could jump and land on, assuming she remains in a spin jump pose. Breaking spin and aiming down will gain an extra 2 pixels.

The dashed lines indicate the jump without Speed Booster (or with zero dash frames).

Water Physics

Water jump velocity.png

Water jump height.png

The dashing distance is required to be in air physics before entering water physics. After entering the water, additional frames do not contribute to jump height.

The air and water plots have the same axes, so they can easily be compared.

Writeup from FreyasSpirit on why this chart is non-linear

See also