What Mega Evolution changes
Gyarados, number 130 in the National Dex and a Kanto Pokémon,
holds Gyaradosite to become Mega Gyarados,
taking its total from 540 to 640. The biggest single gain is 30 Attack, followed by 30 Defense. Nothing goes down — HP and Speed stay exactly where they were.
The typing changes: it gains Dark and drops Flying, which rewrites every matchup below. Mega Evolving replaces Intimidate and Moxie with Mold Breaker.
What gets through
As Water and Dark, 5 of the eighteen attacking types get through for extra damage. It resists 6 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.
On the Regulation M-B ladder
Mega Gyarados is played on 0.48% of teams in the Regulation M-B VGC
ladder, which puts it 101th of the 282 Pokémon with enough games to
measure. The move almost every one of them carries is Waterfall at 95.8%.
The Champions module tiers it UU.
Those figures come from Smogon's published usage statistics rather than from anything measured
here, and they describe what the ladder plays, not what is strongest.
What threatens it
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 Gyarados takes extra damage from.
- Charizard-Mega-Y — Solar Beam (Grass, ×2), on 82.2% of its sets
- Sinistcha — Matcha Gotcha (Grass, ×2), on 97.9% of its sets
- Whimsicott — Moonblast (Fairy, ×2), on 93.9% of its sets
- Sneasler — Close Combat (Fighting, ×2), on 99.7% of its sets
- Farigiraf — Thunderbolt (Electric, ×2), on 59.2% of its sets
- Floette-Mega — Dazzling Gleam (Fairy, ×2), on 95.9% of its sets
Where it sits among the Megas
Of the 91 Mega forms in the dex, Mega Gyarados is 20th by base
stat total. Its best stat is Attack at 155, which is 16th
among Megas; its worst is Sp. Atk at 70, 72nd.
2 other Megas share the Water and Dark typing and therefore this exact matchup board: Mega Greninja, Mega Sharpedo.
The unevolved Gyarados is itself on 0.30% of teams.
Putting it on a team
A Mega slot is a commitment: the stone occupies the held item, so whatever Mega Gyarados 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
155 points of
Attack actually change a
knockout.
