What it does
Plus raises the holder's Special Attack by 1.5× whenever an ally in battle has the Plus or Minus ability. The boost activates automatically — no move required, no turn spent.
This is purely a doubles ability. In singles, there is no ally, and Plus does nothing.
The trigger is symmetrical: two Plus users together both activate each other's boosts. A Plus user next to a Minus user activates both boosts simultaneously. Either configuration works.
For Dedenne specifically: 81 base Special Attack becomes roughly 122 when Plus is active. That sits above most un-boosted mid-tier Special Attackers and reaches a point where it can meaningfully threaten many targets. It's not elite, but it's real.
Uncertainty flag: The active pool of Minus holders available in Champions Reg M-A may vary. Building around a specific Plus/Minus pair should be verified against current roster data before committing to a team.
Who runs it
Dedenne carries Plus in 41% of its Champions sets. Electric/Fairy typing covers two relevant offensive niches — Electric hits Water and Flying, Fairy hits Dragon, Dark, and Fighting. Speed sits at 101 base, which is fast enough to outrun a wide range of threats once Plus is active.
Partner options: two Dedenne together work, each triggering the other's boost. Any Minus user that can stay on the field alongside it also works. The team-building task is finding which of those partners fits the rest of your squad.
How to use it
Bring both your Plus/Minus pair out at the same time. Plus activates automatically once they're both on the field. From there, use Dedenne's Electric and Fairy special moves with the boosted Special Attack.
With 101 base Speed, Dedenne can often move before opponents respond after entering. That speed advantage matters because your priority is dealing damage before the opponent removes your partner.
The biggest threat to this setup is your partner going down. If your ally faints, the Plus boost ends immediately, and Dedenne drops back to 81 Special Attack. At that point it can still act — 101 Speed and Fairy/Electric coverage remain — but the damage output drops noticeably.
Tips & strategy
Plan for the partner going down. What does Dedenne do at 81 Special Attack? If the answer is 'very little', you need another way to keep the partner in, or a backup plan for Dedenne's solo turns. Having a Fairy-type move for late-game cleanup against Dragon types can justify keeping it around even after the boost is gone.
Paralysis cuts Speed. If an opponent uses Thunder Wave on Dedenne, your speed advantage disappears and the activation window for Plus becomes harder to use efficiently. Keep that in mind if you're facing teams that run heavy status support.
The Plus/Minus system is a niche archetype — its ceiling depends entirely on how well the pair covers each other's weaknesses, not just the raw stats. Teams that deal with it successfully usually just target the weaker of the two partners first. Build with that aggression in mind.