Main Power Up

Main Power Up is an ability in Splatoon 2 added in the update.

The ability appears in both primary and secondary gear slots, and will have different effects on each main weapon, even inside the same weapon class.

All gear previously available in the shops that had are now available with Main Power Up.

Known effects
The effects of Main Power Up are displayed on the Equipment screen on the info tab for the abilities for the currently selected main weapon. The benefits from Main Power Up will vary from weapon to weapon. Weapons which acquire increased damage are incapable of decreasing the number of hits required to splat an undamaged opponent, but the damage total for each hit will be slightly increased.

Some weapons receive an increase in bullet velocity, which means they also get more range.

Shooter

 * - Increases shot accuracy when firing while jumping by up to 50% and lessen shot spread variance when firing while on the ground.
 * - Increases damage by up to 25%.
 * - Increases ink coverage by up to 16.7%.
 * - Increases shot accuracy when firing while jumping by up to 40% and lessen shot spread variance when firing while on the ground.
 * - Increases shot accuracy when firing while jumping by up to 50%.
 * - Increases damage by up to 24%.
 * - Increases bullet velocity by up to 8.5%. Increases accuracy while on the ground by up to 30%.
 * - Increases damage by up to 30%.
 * - Increases high-damage radius of explosions by up to 200%.
 * - Increases ink coverage by up to 13.8% and lessen shot spread variance when firing while on the ground.
 * - Increases shot accuracy when firing while jumping by up to 37.5%. Increases the radius of explosion.
 * - Increases shot accuracy when firing while jumping by up to 50%. Increases the radius of explosion.
 * - Increases shot accuracy when firing while jumping by up to 50%.
 * - Increases damage by up to 25%.
 * - Increases shot accuracy when firing while jumping by up to 50% and lessen shot spread variance when firing while on the ground.
 * - Increases ink coverage by up to 20.2%.
 * - Increases damage by up to 21.6%.
 * - Increases damage by up to 25%.
 * - Increases damage by up to 30% while tapping, and 20% while holding.

Roller

 * - Increases damage by up to 15%.
 * - Increases damage by up to 15%.
 * - Increases damage by up to 15%.
 * - Increases movement speed by up to 5%. Increases ink coverage while inking.
 * - Slightly increases movement speed by up to 12%. Increases ink coverage while inking.
 * - Increases damage by up to 15%.

Charger

 * - Increases damage by up to 20%.
 * - Increases range. Increases ink coverage by up to 24%.
 * - Increases range. Increases ink coverage by up to 17%.
 * - Increases range. Increases ink coverage by up to 17%.
 * - Increases damage by up to 15%.
 * - Increases damage by up to 20%.
 * - Increases damage by up to 20%.

Slosher

 * - Increases ink coverage.
 * - Increases ink coverage.
 * - Increase damage from higher grounds.
 * - Increases ink coverage.
 * - Increases ink coverage.

Splatling

 * - Increases damage by up to 10%
 * - Increases duration of firing in a burst.
 * - Increases damage by up to 10% when not fully charged and up to 20% when fully charged.
 * - Increases duration of firing in a burst.
 * - Increases duration of firing in a burst.

Dualie

 * - Increases damage by up to 20%.
 * - Increases damage by up to 20%.
 * - Increases damage by up to 20%.
 * - Increases damage by up to 20%.
 * - Increases damage by up to 16%.

Brella

 * - Speeds up Brella canopy regeneration.
 * - Increases Brella canopy durability.
 * - Speeds up Brella canopy regeneration.

Gear
Main Power Up is the main ability of:

Calculating damage
A = ability points = 10 × [Main Power Up main slots] + 3 × [Main Power Up sub slots] B = (3.3 * A - 0.027 * A^2) / 100 C = (mid - min) / (max - min) D = min⁡ + ( max - min ) * lerpN(B, C) result = [base value] * D

and  can be found in the game's parameters as DamageRate_MWPUG_High and DamageRate_MWPUG_Mid. For Main Power Up,  is always 1.0.

lerpN is an interpolation function where: If C = 0.5 then lerpN(B, C) = B If B = 0.0 then lerpN(B, C) = B If B = 1.0 then lerpN(B, C) = B If C ≠ 0.5 then lerpN(B, C) = e^(-(ln⁡(B) × ln⁡(C)) / ln⁡(2))

For example: Splat Dualies with two primary Main Power Up slots and one secondary Main Power Up slot. Given: main slots = 2 sub slots = 1 min = 1.0 mid = 1.06 max = 1.16 base damage = 30

A = 10 × 2 + 3 × 1 = 23 B = (3.3 * 23 - 0.027 * 23^2) / 100 = 0.503985906 C = (1.06 - 1) / (1.16 - 1) = 0.375 C ≠ 0.5, so lerpN(B, C) = e^(-(ln⁡(B) × ln⁡(C)) / ln⁡(2)) effect = 1 + ( 1.16 - 1 ) * e^(-(ln⁡(0.503985906) × ln⁡(0.375)) / ln⁡(2)) = 1.080637745 result = 30 * 1.080637745 = 32.41913235 This would appear as 32.4 damage in-game.

Damage cap
After the damage cap is reached, adding more Main Power Up will not increase maximum weapon damage. It will continue to increase falloff damage. For example, even if a Splattershot Pro reaches 49.9 damage on direct hits within effective range, the lower-damage hits that occur out of effective range will still continue to be boosted by using more Main Power Up.

Trivia

 * Main Power Up is one of first two abilities to be added to the game post-release. It however remains as the only truly unique ability, unlike Bomb Defense Up DX.