Double Bomb Jump

A double bomb jump (DBJ) is a type of bomb jump. The double bomb jump is actually one of the only bomb jumps which is provably intended by developers, being required in a few puzzles and one of the NTSC attract demos. A double bomb jump has two main types: a regular double bomb jump which goes straight up, and a "laddered" Double Bomb Jump. 

To perform a double bomb jump, place a bomb on the ground where you are. Shortly before it explodes (a visual cue is almost immediately after the bomb animation disappears completely before exploding), lay another one. 

At the peak of your jump, but before you start descending, lay your final bomb. The second one you laid will boost you up, and then the final one you laid will hit you in midair. 

Laddered Double Bomb Jump

To performed a laddered double bomb jump, do this process, but add some lateral movement into it. A basic explanation of inputs is holding the control stick forward slightly before the first bomb explodes, and then holding back after you place the final one and keep holding back for a short moment after landing. Once landed, roll backward a short distance and then roll forward (or in whatever direction you were jumping toward) as much as possible to hit the second bomb you placed. Keep holding forward the rest of the jump.

Metroid Prime

Laddered double bomb jumps are used and required in many locations in 21% runs, such as Phazon Processing Center, Phendrana's Edge, Frozen Pike, and Phazon Core. 

Metroid Prime 2: Echoes

Double Bomb Jumps are also prevalent and required in normal gameplay in Prime 2, but can also be used in many rooms without the Space Jump Boots.

Metroid Prime 3: Corruption

Just like the previous two games, DBJs are used in this game, though to a lesser extent. Bomb Jumps in this game can be replaced with Spring Ball. For a Double Bomb Jump, flick the Wii Remote upwards to use Spring Ball and lay a Bomb at the peak, then use Spring Ball again before the Bomb explodes to gain the extra height.