Trait rerolling starts at the Traits NPC in the Upgrades area. Walk to the NPC, open the trait menu, choose a unit, and spend Trait Shards to roll. Auto Reroll uses a configuration menu, but auto rolling works best when you know exactly which result you want. If you turn it on without a target, the system can burn shards faster than you notice and leave you with a result that is not better for the unit.
Pick the unit before picking the trait. A reroll on a temporary filler unit is usually a bad trade because the unit may leave your team after the next banner pull. Reroll on a carry that clears waves, a boss killer that stays deployed in difficult stages, a tank that keeps lanes stable, or a support unit whose effect matters in your main team. If a unit only fills a slot for one or two early Story stages, keep your shards and replace the unit later.
Decide what problem the trait needs to solve. If the unit is your main damage source, look for a result that raises damage, attack speed, range, crit pressure, or another direct damage condition confirmed by current trait data. If the unit is a farm or economy piece, a damage trait may not fix the account's real problem; a money or placement-related trait can matter more. If the unit is a tank, survival and base-protection value can beat a small damage increase. The rarest word in the list matters less than making the unit better at the job it already performs.
An imperfect trait is not always worth rerolling. The expensive mistake is turning a workable trait into nothing after several rolls. If your carry gets a trait that improves damage or range, use that power to clear more stages before chasing a perfect result. If your account still needs basic perks, gear, or more units, perfection rolling can trap progress inside one menu. Stop early when the roll changes a loss into a clear.
Be careful with sub-traits. The reroll menu does not lock a main trait or sub-trait right now. That means a good main trait can disappear while you chase a better sub-trait, and a good sub-trait can disappear while you chase the main result. Combined perfect results are late-game luxury rolls. For normal progression, keep the first roll that supports the unit's role and spend the saved shards on another permanent unit.
Auto Reroll works only with a strict target. Before using it, open the config, choose the result you are willing to stop on, and check that you have enough shards to survive a bad streak. Leaving auto rolling active while distracted can burn a shard stack quickly. If the config is wrong or the target is too rare for your shard stack, the account can lose a large amount of reroll currency without a stage-clear improvement.
Farm more Trait Shards after your team is stable. Trait Reroll or shard-related routes can include Raid Shop, Squadron, and selling banner summons, but these routes can shift with updates. Use them as a way to support a trait plan, not as an excuse to reroll every unit. The practical route is simple: identify the unit that blocks progress, roll until it gets a role-matching trait, then return to Story, raids, or material farming to test whether the roll actually helped.