Ability chunk

Ability chunks are a currency in Splatoon 2. They can be acquired from Murch or as a reward from Salmon Run. They are used by Murch to add secondary abilities to gear.

Obtaining chunks
Ability chunks can be obtained from green capsules that are rewarded in Salmon Run. Ordinary green capsules have a 40% chance to contain two ability chunks and a 10% to yield four, while shiny green capsules guarantee four chunks. Gear rewards can also be exchanged for the abilities present on the given gear, turning those sub abilities into chunks.

Murch has the option to scrub any gear the player has, where the secondary abilities are "scrubbed" off and turned into chunks that the player obtains with the cost of cash (or  cash when scrubbing the Splatfest Tee). The player also gains chunks when rerolling gear, where the previous sub abilities are turned into chunks.

As of Version, the player was able to earn ability chunks from the Splatfest Tee if all the slots were already filled out, as the shirt continued filling in experience points, which awarded a random ability chunk every 7500 points.

Adding abilities
Multiple chunks are required to add one secondary ability to a piece of gear. For example, if the player is looking to add one secondary ability of Run Speed Up, they would need ten Run Speed Up ability chunks.

The price depends on the number of the same secondary ability already present on the gear. The primary ability is not counted for this calculation. When the ability a player wants to add is not present on the gear, it costs ten ability chunks to fill a slot with the ability. If one copy of the ability is present, the cost is twenty chunks. If two copies of the ability are present, it costs thirty chunks. If there was an ability that got replaced, it turns into a chunk.

Uses
Ability chunks are a more reliable method for acquiring sub abilities than re-rolling gear or using drinks from the Crust Bucket. Due to this, they are often used for stacking abilities or getting abilities that are unlikely to appear in a re-roll.