Damage Boost

Damage Boost is a mechanic that involve taking damage to increase jump height.

The player can take damage from fire, lava, cacti, falling, status effects, etc...

Damage is usually disabled on parkour servers, so this trick is rather used in Singleplayer, or speedruns.

WIP

Fire/Cactus Damage Boost
The most widely known and used damage boost, which is performed by taking damage before the peak of the jump.

[Details, jump height]

Taking Damage on a Slime Block
Taking damage while falling increases the player's downward speed, which is not useful unless it can be converted the other way around by bouncing on a slime block. [Formula for knockback]

Jumping from the edge of a block makes it so the player takes maximum downward knockback when damaged.

Taking Damage with Jump-Boost
This last variant is very situational as it only concerns Jump-Boost levels 252 - 256. [WIP]

As a side note, Jump-Boost levels 128 - 249 can also be abused on slime blocks: by simply jumping, the negative jump boost is converted into a massive bounce. Levels 250 and 251 can neither make the player jump nor bounce.

Some Singleplayer parkour maps use Jump-Boost 255 to negate fall damage, which can be abused with this glitch.