Mega Diancie
Rock · Fairy · 700 BST · Diancite
| Stat | Base | Mega | Relative size | Change |
|---|---|---|---|---|
| HP | 50 | 50 | — | |
| Attack | 100 | 160 | +60 | |
| Defense | 150 | 110 | -40 | |
| Sp. Atk | 100 | 160 | +60 | |
| Sp. Def | 150 | 110 | -40 | |
| Speed | 50 | 110 | +60 | |
| Total | 600 | 700 | +100 |
| Stat | Base | Mega | Relative size | Change |
|---|---|---|---|---|
| HP | 50 | 50 | — | |
| Attack | 100 | 160 | +60 | |
| Defense | 150 | 110 | -40 | |
| Sp. Atk | 100 | 160 | +60 | |
| Sp. Def | 150 | 110 | -40 | |
| Speed | 50 | 110 | +60 | |
| Total | 600 | 700 | +100 |
Diancie, number 719 in the National Dex and a Kalos Pokémon, holds Diancite to become Mega Diancie, taking its total from 600 to 700. The biggest single gain is 60 Attack, followed by 60 Sp. Atk. It also loses 40 Defense and 40 Sp. Def.
The typing does not change — it is Rock and Fairy before and after — so the Mega is the same defensive problem as the base form, only bigger. Mega Evolving replaces Clear Body with Magic Bounce.
As Rock and Fairy, 4 of the eighteen attacking types get through for extra damage, and Steel lands for quadruple. It resists 5 and is outright immune to 1. The full board is above; the short version is that the types listed under ×2 and ×4 are the ones worth planning around.
Mega Diancie cannot be used in the current Pokémon Champions regulation, so there is no ladder data for it and no legal set to report. Diancie is not legal either, so the whole line sits outside the format rather than just the Mega.
Regulation M-B closes on 9 September 2026, and legality is regenerated from the format data on every build rather than written by hand, so this page will change on its own if that changes.
Smogon publishes no head-to-head checks-and-counters data for doubles formats, so this list is computed, not measured: these are the most-played Regulation M-B Pokémon carrying a damaging move of a type Mega Diancie takes extra damage from.
Of the 91 Mega forms in the dex, Mega Diancie is 11th by base stat total. Its best stat is Attack at 160, which is 12th among Megas; its worst is HP at 50, 91st. No other Mega Evolution has the Rock and Fairy typing, so this matchup board is unique to it.
A Mega slot is a commitment: the stone occupies the held item, so whatever Mega Diancie would have wanted from an item, it does not get. Drop it into the team builder to see what the rest of the six then have to cover, or take it to the damage calculator to find out whether those 160 points of Attack actually change a knockout.