There are two ways that players can go about increasing the Star Power of their gear in Splatoon 3: they can find a duplicate of the item in the relevant shop, or they can have Murch perform the act. Raising a gear's Star Power is not cheap, though, and fans may want to have more information about the mechanic before they engage with it. Providing that information is the precise purpose of this guide, and fans will find details on Splatoon 3's Star Power in what follows.
Splatoon 3: How Does Star Power Work
Increasing a piece of gear's Star Power will do one of two things, and exactly what it does is determined by the state of the gear that is being improved. More specifically, if the item has two ability slots or less, raising its Star Power will give it another of those slots. This is undoubtedly a powerful effect, and it is recommended that Splatoon 3 players increase the Star Power on the headgear, clothing, and shoes that they plan to use.
Once a piece of gear in Splatoon 3 has all of its ability slots unlocked, players can continue to raise its Star Power in order to increase the rate at which it gains XP. However, the XP modifier that is attached to increasing the Star Power of items with three slots is quite small, and Reddit user azurnamu indicates that it is calculated with this formula: 1.0 + (star power - ability slots + 1) * 0.3. This means that if a player were to raise the Star Power of a 2-star piece of gear with three slots, it would gain an XP modifier of 1.03.
While this slight-increase to XP acquisition can assist with some tasks, such as farming ability chunks in Splatoon 3, it is not particularly significant. As such, players that have other uses for their Cash may want to put Star Power upgrades for gear pieces that have all their ability slots unlocked on hold.
To note, there are Brand Badges in Splatoon 3 that offer some incentive for players to increase the Stars on their gear. More specifically, each of the game's brands has two associated Badges, which are awarded when a fan collects 30 Stars and 100 Stars in gear from them. That said, it is almost certainly more economical to pursue these Badges by purchasing an abundance of gear with low Star counts rather than repeatedly increasing the Star Power of acquired items.
Splatoon 3 is available for Nintendo Switch.