Union Arena's 3on3 Colorful Kyurun Cup hits Tokyo Big Sight Oct. 18

Union Arena marks its 3.5th anniversary with a live event on Sunday October 18, 2026, at Tokyo Big Sight, West Hall 4. The event is titled "3.5th Anniversary Iori Moe Festival #Colorful Kyurun Cup." Its centerpiece is a 3on3 team battle, with the ONE BATTLE CUP and Matching Battles as side events. Moe Iori, whose name appears in the event title, is the host (MC) of the official stream show "Uniari Up!".

How the 3on3 works

Entry was by advance application only, through the BANDAI TCG+ app, and applicants had to register a face photo on the app first. Photo screening can take more than one week. The 3on3 application period ran from Friday September 4, 2026 to Sunday September 27, 2026.

A team has 3 players, and each member must play a different title. Teams of 1 or 2 cannot enter, and members may confer during matches. Registration has two steps. One representative applies and receives a team ID, and the other members then enter that ID. Each person applies with their own BANDAI TCG+ account, proxy applications are prohibited, and applicants under 18 need parental consent.

The format is called "ONE Color Battle." The team picks one color, and every member must use a deck of that color. Each deck may include up to 4 cards outside the chosen color. New card numbers released or distributed fewer than 7 days before the event are allowed. Decks must be registered by check-in or the team cannot take part, and decks cannot be changed during the event. Swapping decks between teammates is prohibited.

The tournament is a Swiss draw of 6 rounds at most. Each match is a single game with a 30-minute limit. All three members play one game each against the opposing team, and the three games start at the same time. A game undecided at the time limit counts as a loss for both players.

A team wins a round with 2 or more individual wins and earns 1 point. Results such as 3-0 and 2-1 count as wins, including 2 wins with 1 double loss. Results such as 1-2 and 0-3 earn 0 points. In a 1-win, 2-double-loss result, the single win is also treated as a double loss.

Standings are decided by points, then OP% (the average win rate of opposing teams), then OP2% (the average point rate of the opponents' opponents). If all three are equal, a random method chosen by the organizers decides.

Team Uniari Up! and its restricted decks

A special "selfish rule" reserves certain decks for one team. Decks that reached the BEST8 of Union Arena Festival 26-27 or Union Arena Tour 26 can be used only by "Team Uniari Up!" Festival 26-27 counts two venues, June 28 in Makuhari and August 22 in Hyogo. Tour 26 counts August 1 in Sendai.

The team is formed by Dan Shiojima and Daiki Haraguchi, Moe Iori's guests on the official YouTube show "Uniari Up!" It enters the 3on3.

As of Friday October 9, 2026, the restricted BEST8 decks are:

• Purple The iDOLM@STER Shiny Colors
• Green Mushoku Tensei: Jobless Reincarnation
• Purple Rebuild of Evangelion
• Red Rebuild of Evangelion
• Purple The Eminence in Shadow
• Purple Arknights
• Blue Macross series
• Yellow SAKAMOTO DAYS
• Green Kamen Rider
• Blue Code Geass: Rozé of the Recapture
• Blue The iDOLM@STER Cinderella Girls

Prizes

Prizes go to each team member. An undefeated team receives 1 Union Rare card (WINNER ver.) and 2 "Moe Iori Action Point Card vol.4" promo cards. Teams with 1 loss, the top finishers, receive 1 promo card.

Every 3on3 participant receives 1 "Moe Iori Action Point Card vol.4" promo card and 1 serial-code Uniari Ticket (Set 6). Those who answer the survey receive 1 serial-code Uniari Ticket (Set 6).

A random prize adds one more route to the promo. One team per color, chosen from the teams that have not retired by the end of round 6, receives 1 "Moe Iori Action Point Card vol.4" promo card.

ONE BATTLE CUP and side events

The ONE BATTLE CUP application period ran from Friday September 11, 2026 to Sunday October 4, 2026, via BANDAI TCG+. It is played under ONE Battle rules, and each tournament is limited to specified titles: HUNTER×HUNTER, BLEACH: Thousand-Year Blood War, Goddess of Victory: NIKKE, Gakuen iDOLM@STER, and The iDOLM@STER Shiny Colors.

It is a Swiss draw of up to 6 rounds in triple-elimination style. Each match is a single game with a 25-minute limit, and an undecided game is a loss for both players. A win scores 3 points and a loss 0. Tiebreakers run through the opponents' win rate (OMW%), the average OMW% of the opponents' opponents, and then a random method chosen by the organizer. An OMW% below 0.33 counts as 0.33.

Prizes depend on results and on the title entered. Swiss pods run in units of 64 players, and the size varies with turnout. With 128 players, 1st–2nd place get the winner prize and 3rd–16th place get the BEST8 prize.

The side-event schedule is Matching Battle 11:00–18:30, a Re:Zero cast early-access battle 15:45–16:45, and a Moe Iori two-shot photo session 17:15–18:00.

Merchandise lottery and venue rules

On-site merchandise is sold by lottery to people who check in at the venue. Entry runs from doors open to 12:00, winners are announced around 12:00, and winners can buy from 12:30 to 17:30. Only participants in the 3on3, the ONE BATTLE CUP, or a side event can buy, and only lottery winners can use the merch sales.

Five booster products are on offer, though the lineup may change:

• Macross Series Vol.2 [EX14BT]
• The iDOLM@STER Cinderella Girls [UA55BT]
• Tengen Toppa Gurren Lagann [UA56BT]
• BLEACH: Thousand-Year Blood War Vol.3 [EX15BT]
• Steins;Gate [UA57BT]

Sales are by the box only, with no single packs. Each entrant may apply for 1 of the 5 products, and each winner may buy up to 1 box. Stock is limited, no items are held, and no other products are sold.

The venue is cashless only. Accepted methods include major credit cards, transit IC cards such as Suica and PASMO, QR-code payments such as PayPay and Alipay+, and e-money (iD, QUICPay). No prices are stated.

Changes or cancellation would be announced on the official X account @UNION_ARENA_TCG. Trading or selling inside the facility is prohibited, as is eating in the venue, though drinks are allowed. Copied cards and cards with writing added cannot be used.

Where it fits in the calendar

TCGKing's release calendar for Union Arena lists Re:ZERO Vol.2 EX17BT for October 30 at 385 yen. How the event's Re:Zero cast early-access battle relates to that release is not spelled out.

What is still unknown

Box prices for the five merchandise products are not given. Neither is the participant cap for the 3on3 or the number of teams. The start and end times of the 3on3 main tournament are not stated, and neither are the exact ONE BATTLE CUP winner and BEST8 prizes. The Union Rare WINNER ver. card is not described in text.

What it means for players

• The event is in Tokyo, and entry was by advance application only. Both application windows, for the 3on3 and the ONE BATTLE CUP, have closed.
• For anyone on site, the lottery entry cutoff is 12:00, and each entrant may apply for only 1 of the 5 products.
• Bring a cashless payment method, since no cash is handled.
• Because new card numbers released or distributed fewer than 7 days before the event are legal, a deck registered at check-in can include the newest cards.