Mega Gyarados ex Deck
0.2% of the meta · Updated September 8, 2026
Signature card
Mega Gyarados ex
Immersive
Strengths
- Mega Blaster's 140 damage 2HKOs nearly every non-Mega attacker while the deck-discard creates a secondary win condition.
- Mantyke provides a cheap, expendable bench option that limits the opponent to only 1 point if they KO it, preserving Mega Gyarados ex's health total.
- Protective Poncho attached to a benched Basic shields it from all opponent attack and ability damage while it sits on the bench, protecting key setup Pokemon like Magikarp.
Weaknesses
- Mega Gyarados ex is a Mega; the opponent wins immediately if it is KO'd, scoring 3 points in a single knockout.Mega KO = lose
- Both copies of Mega Gyarados ex need Magikarp to evolve from; losing both Magikarps before evolving eliminates the main win condition.Consistency
- Palkia ex and Stoutland can apply enough pressure or disruption to prevent Mega Gyarados ex from attacking before it is KO'd.Matchup
- Retreat cost of 3 makes Mega Gyarados ex very difficult to swap out once it is damaged, trapping it in the Active spot.Deckbuilding
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Est. 301 packs to collect all core cardsdetails
Core Cards
Key Moves & Abilities
Strategy Guide
Auto-generatedMega Gyarados ex attacks with Mega Blaster for 140 damage while discarding the top 3 cards of the opponent's deck each hit, combining raw KO power with a deck-out secondary win condition. Each Mega Blaster KO scores you 1 point on non-ex targets or 2 points on ex targets — but if Mega Gyarados ex is KO'd, the opponent wins immediately by scoring 3 points.
Use Poké Ball to find Magikarp on turn 1 and begin attaching Water Energy. The Magikarp-to-Mega Gyarados ex evolution must come through natural draw via Professor's Research or Copycat since Poké Ball cannot search evolved forms; Lisia can surface Basic Pokemon with 50 HP or less such as Mantyke or Feebas to fill the bench. Feebas and Milotic, or Frillish and Jellicent in the top build, function as secondary Water attackers and bench targets while Mega Gyarados ex charges up. Once live, Mega Blaster hits 140 damage per turn — a clean 2HKO on anything in the format — and shaves 3 cards from the opponent's deck each attack, accelerating a deck-out threat. Sabrina sends the opponent's Active to the bench so they must pick a new Active, and Irida heals 40 damage from each of your Water Pokemon that has Water Energy attached, extending Mega Gyarados ex's longevity.
Damage Math
Any Active Pokemon
140 base (no modifier) + 3 cards discarded from opponent deck
2HKO on all non-Mega Pokemon; deck-out pressure compounds each turn
How to Play
Protect the Magikarp Evolution Path
Your entire deck collapses if Mega Gyarados ex never hits the field. Lead with Mantyke or a secondary attacker as your Active to absorb early hits while Magikarp sits safely on the bench evolving. Use Professor's Research and Copycat on the turns you need draw most. Poké Ball finds Magikarp only — the Mega evolution itself needs to come from natural draw.
Apply Dual-Win-Condition Pressure
Once Mega Gyarados ex is active, every Mega Blaster swing damages the opposing Pokemon for 140 and discards 3 deck cards. Over four attacks that is 12 discards. Against thin decks this forces a deck-out win without needing to score the final KO. Use Sabrina to send a dangerous Active Pokemon to the bench so the opponent must choose a weaker replacement.
How to Beat This Deck
KO Magikarp Before It Evolves
Mega Gyarados ex cannot enter the field if Magikarp is KO'd first. Spread bench damage to hit Magikarp before it evolves. Cyrus can force a damaged Magikarp from the bench into the Active Spot so you can finish it off for 1 point, collapsing the entire win condition.
Build a Thick Deck to Outlast Deck Discard
Mega Blaster discards 3 cards per attack. A deck that started with 20 cards can run out in roughly 6 turns of Mega Blaster attacks. Avoiding excessive trainer thinning before the matchup keeps your deck large enough that the discard never reaches 0 before you score 3 points through normal KOs.
Field Non-ex Attackers to Score 1 Point Per KO
Mega Gyarados ex awards 3 points — an instant win — when KO'd, so never attack into it recklessly. Instead, field non-ex attackers that score 1 point each for the opponent to KO while you set up a counter-strategy. This forces the Mega Gyarados ex player to spend multiple turns KO'ing your non-ex targets to reach 3 points.
Common Substitutions
Secondary Water bench body
- Frillish:Appears in top build as a lower-evolution bench filler that provides Water type synergy
- Feebas:Medoid list alternative; evolves into Milotic for an additional attackable secondary line
Matchups
Threats — Weak Against
Based on type weakness analysis of core cards. View full matchup matrix →