Union Arena Attack on Titan Eren Deck Guide: Red Vol.2

Updated October 19, 2026: rebuilt around the post-Vol.2 store results on unionarenadecklists.com. The old version recommended the 104th Cadet Corps shell from a September 10 list count, before Vol.2 was even out, and gave matchup and mulligan advice that no result backed up.

The Union Arena Attack on Titan Eren deck guide list: Rumblerama winner

This is bag_of_sand's winning list from Rumblerama (September 25). The last column counts how many of the nine placed Red Eren lists since Vol.2 play the card at all.

That's 35 characters, 11 events and 4 sites. Ten card numbers are in all nine lists, so the core is settled. The flex slots are where bag_of_sand went their own way: Conny, Grisha and Jean are in no other placed list, and it's the only one of the nine with no Hange Zoë (AOT-1-069), which the other eight all run.

Chart: ShonenTCG. Source: unionarenadecklists.com Eren Jaeger page, store-event placings September 20 to October 5, 2026, deduped by player and event; card energy from Bandai's card list.

Why each card is in the Red Eren deck

The Raid targets. Both Attack Titans Raid onto a character named Eren Jaeger, so the deck plays a lot of plain Erens. AOT-1-090 is the free one: no effect, zero energy, and its Get trigger adds it to your hand. Eren AOT-1-106 is a three-energy body that gains 1000 BP at 3 or less life, and it's on the energy line for a reason we'll get to. Eren AOT-2-070 looks at the top three cards for a 104th Cadet Corps card and then makes you sideline one from hand.

The two Titans. Eren Jaeger (Attack Titan) AOT-1-094 costs eight energy and deals 2 damage when it hits directly. Once per turn on the front line it sidelines an enemy with 2000 or less BP, and when it attacks you pick: Impact 1, or (at 3 or less life) it stands back up. The seven-energy AOT-2-072 gains 1000 BP until your next turn and sidelines something when played: 3000 BP or less, or 5000 or less if you pull a life card into your hand or are already at 3 life. Both have Raid triggers, so flipping one from your life area lets you Raid it on the spot if you have the energy.

The Basement engine. Key to the Basement looks at the top five for Basement or any Inheritor of the Titan card (both Attack Titans qualify), and if what you take has 6 or more base required energy it stands one of your AP cards back up. So a Key that finds a Titan or Basement costs you nothing in actions. Basement is a six-energy site that draws a card and sidelines one, and it costs two less while a Key to the Basement is in your sideline. The deck pitches cards to the sideline constantly (Armin AOT-1-075, Eren AOT-2-070, Grisha and Basement all do it), so that discount is easy to switch on.

Image: Bandai, UNION ARENA official card list (UE10BT/AOT-1-094, UEX07BT/AOT-2-072, UE10BT/AOT-1-098).

The events. Hardened Punch sidelines an enemy with 5000 or less BP and costs 1 AP instead of 2 with an Eren on your field. It also shields a Raided Attack Titan from Special triggers for the turn. Dedicate Your Heart!! stands two AP cards back up, and its trigger puts a card back into your life area if you're at zero. The one Omni-Directional Mobility Gear is a leftover from the bounce build.

How to get to eight energy

This is the part that trips people up. Raid from hand needs the full required energy on your energy line, which holds four cards at most. Four one-energy bodies give you four. The deck gets to eight because some cards generate more than one: Basement makes three red energy, Eren AOT-1-106 and Hange two each, Jean two. Basement, AOT-1-106 and two more Erens is already seven, enough for AOT-2-072; add Hange instead of a one-energy Eren and you're at eight for AOT-1-094.

With 11 zero-energy characters, you open with at least one in about five hands out of six. Counting the six Titans plus the four Keys and two Grishas that dig for them, nearly nine opening hands in ten have one of those twelve cards. Player One gets 1 AP on turn one, so the early turns are about bodies on the energy line; the Titans come down once the line is built.

Team Sleeveless covered the nine Vol.2 Attack on Titan decks on release day, Attack Titan and 104th Cadet Corps among them. For a game in motion, Dplaystcgs tested Red Attack Titan best-of-three against Green Marleyan Warriors:

Bandai's two Red recipes

Bandai posted two Red Attack on Titan recipes on September 10. One is the 104th Cadet Corps build: Eren AOT-1-092, four Mikasa AOT-2-067, four Omni-Directional Mobility Gear, and a lot of returning your own characters to hand. The other is an Attack Titan build with AOT-2-072, both Vol.1 Titans, Hardened Punch, Hange and Armin AOT-1-077, but no Basement or Key. The players who placed took the second idea and bolted the Basement engine on. Eren AOT-1-092 is in about a quarter of all public Red Eren lists since Vol.2 and in none of the nine placed ones.

What it's up against

There's no Attack on Titan deck in Bandai's Regional top fours, and store events don't post round-by-round results, so we can't give you matchup win rates. The nine placings are small events: two wins (Rumblerama and a Midgard Gaming weekly), a 2nd at Timemasters, a 3rd at Rumblerama, a 4th, and four finishes from 7th to 15th.

Our take

We'd build bag_of_sand's list with one change: swap Conny and Grisha for two Hange, because every other placed list runs her: she makes two energy on the line and draws a card once an Eren is out. Keep all four Basements and all four Keys; they're the reason the deck can Raid an eight-drop at all. Skip the 104th Cadet Corps bounce build for now. It's fun, it's Bandai's own recipe, and nobody's placing with it.

How we checked this: on October 19, 2026 we pulled all 353 public Red Eren lists from unionarenadecklists.com, kept the store-event placings since September 18 (nine after removing duplicates), tallied every card, read each card's text and energy on Bandai's English card list, and worked out the opening-hand odds exactly for a 50-card deck.

Related Reading

• Union Arena Attack on Titan Armin Deck Guide: the other Red Vol.2 build.
• Union Arena Raid Mechanic Explained: what happens to the Eren under an Attack Titan.
• Union Arena Deck Building Guide: energy line, AP and the 50-card rules.
• Union Arena Attack on Titan Vol.2 Buying Guide: singles or sealed for this list.

References

• unionarenadecklists.com, Eren Jaeger lists: public lists and store-event placings
• UNION ARENA official card list: card text, required and generated energy
• UNION ARENA Recommended Decks by Title: Bandai's Red Attack on Titan recipes
• UNION ARENA products: Attack on Titan Vol.2 release date