Charge Beam Combos
A Charge Beam Combo - also known as a Power Bomb combo, Power Bomb/beam shield, or special beam attack - is the combination of one of either Ice Beam, Wave Beam, Spazer, or Plasma Beam with Charge Beam and a Power Bomb.
When the beam is charged for 120 frames (2 seconds on NTSC / 2.4 seconds on PAL) while Power Bombs are selected and one other beam is enabled in Samus's inventory, a combo will be performed specific to the beam enabled, which will consume one Power Bomb upon activation.
Except Ice Shield, each individual particle of every combo will deal 300 charged beam-type damage. Ice Shield particles will only deal 90 damage.
While a combo is active, Samus will be unable to use any of her armaments with the exception of Grapple Beam, Power Bombs, and Bombs (only one bomb can be active at a time).
Using Grapple Beam or enabling different combinations of beams while a combo is active may have an effect on the appearance of the combo; however, equipping additional beams while a combo is active will not have an effect on the combo's damage.
Ice Shield
This combo causes four small ice crystals to circle clockwise around Samus. The crystals will disappear when they strike an enemy. Any remaining crystals will fly straight outward on the 20th repetition of the sound effect.
The Ice Shield has uses during a 14% Ice (or similar) run, allowing for optimal fights against Ridley (as part of an opener), Draygon (during initial swoops), and Mother Brain (as an opener, but can potentially be used during redbeam phase as well).
Disabling Ice Beam while this combo is active will cause each of the active particles to deal zero damage as opposed to their normal 90 damage.
Wave Shield
Also known as X-Factor, this combo generates four small purple spheres. If Samus is standing still, the spheres will oscillate in the shape of an X. If Samus is moving, they will orbit her in a wave pattern. The spheres will disappear when they strike an enemy. Any remaining projectiles will vanish partway through the tenth repetition of their sound effect.
This is by far the most effective combo. It is most utilized in Any% and 100% runs against Botwoon and Draygon. If you are using the KPDR route of Any%, X-Factor can be utilized when fighting Phantoon. If you are using the PRKD route of Any%, it can be utilized when fighting Ridley.
Spazer Shield
This combo creates two three-pronged projectiles (similar in appearance to Spazer shots) that begin just above Samus's head. They circle down below her, then circle high above her, and finally rain straight down before vanishing. The projectiles will disappear when they strike an enemy.
Currently, this combo has no known optimal application within a speedrun.
Plasma Shield
This combo causes four large green rings to circle clockwise around Samus. The rings move outward, then inward, and then fly away. Unlike other combos, but like Plasma Beam itself, the rings will cut straight through enemies instead of disappearing.
Currently, this combo has no known optimal application within a speedrun.