Union Arena Card Types and Rarities

By CardSpicy Founder · October 7, 2026

Quick answer

CardSpicy takes the structure from Bandai’s own rule manual rather than from a dealer’s listing, and Bandai publishes both the parts of a card and the parts of a deck. UNION ARENA runs on four card types — character cards, field cards, event cards and Action Point cards — and the rarity labels the publisher prints are C, U, R and SR, with AP cards counted as a separate category in every product’s type list. The deck rule that surprises most people is the one that comes with the card number: every card in a deck must share the same source material code.

The card number is the source here, because it is the thing that decides whether a card is legal in your deck at all.

The four card types

Each type is described in Bandai’s own rule manual, and each behaves differently on the field.

Type	What the rule manual says it does
Character	The cards that attack or block. A character enters the field in Rest Mode and can be placed on either the Front Line or the Energy Line, and it can be moved during the Move Phase.
Field	Cards that mainly provide support. A field card enters in Rest Mode, can be placed on the Energy Line, and cannot be moved to the Front Line. Some field cards are brought into play in Active Mode by their own text rather than in Rest Mode.
Event	One-use cards. An event is played, its effect resolves, and it goes to the Sideline, which is the area the rule manual gives over to used event cards and sidelined characters.
Action Point	A separate resource deck, not a playable card type. Action Point cards sit in the AP Area and are switched to Rest Mode to pay a card’s Action Point cost.

The field itself is worth visualising, because two of the four types are restricted by it. The manual describes the field as the Front Line and the Energy Line together, with a Life Area of seven face-down cards, an AP Area, a Deck Area, a Sideline and a Removal Area. Characters and sites are Active when placed vertically and Resting when placed horizontally, and only Active characters can attack or block.

What a card’s own information block carries

Bandai’s rule manual labels each part of a character card, and the labels are useful because they map onto the deck construction rules as much as onto play.

Required Energy — the number and colour of Activation Energy that must be on your Energy Line before the card can be used. The colour of the requirement matches the colour of the card.
Required Action Points — the number of Action Point cards that must be switched to Rest Mode to play it.
Trait — used by Raid Boosting and by other cards’ effects. Some cards have no trait.
Series name and card number — the two fields that decide deck legality.
Effect and Trigger — the card’s abilities, and separately the effect that can fire when the card is damaged and flips face up in the Life Area.
Activation Energy, BP (Battle Points) and rarity.

One detail about energy is easy to get wrong, and the publisher’s FAQ is explicit about it: energy generation is continuous. It is not spent by playing a card. You only have to satisfy a card’s required energy at the moment you play it, and cards already on the field are unaffected if your generation changes afterwards. The FAQ also confirms that required energy must be met in the matching colour — a green requirement of 5 needs five or more green generation symbols, not simply five symbols.

The rarity labels the publisher prints

Bandai lists the rarity breakdown inside each product page, and the labels are consistent across the line.

Label	What the publisher’s product pages show
C — Common	The largest single block of types in a booster. A recent booster lists 28 types of Common, and an earlier one 35.
U — Uncommon	Also a large block. The same recent booster lists 28 types, the earlier one 35.
R — Rare	The middle tier. Listed at 12 types in the recent booster, 18 in the earlier one.
SR — Super Rare	The scarcest playable tier in the publisher’s breakdown. Listed at 12 types in both cited boosters.
AP — Action Point	Counted as its own category in the publisher’s type list rather than as a rarity of the playable cards, and listed at 12 types in a recent booster.

Two structural notes come out of that table. The first is that Action Point cards are listed separately from the playable cards in every product’s type count, which is consistent with the rule manual treating them as a separate deck rather than as a card type you play with. The second is that the older and newer boosters in this line carry different type counts, so a reader comparing two sets will find 35-turn blocks in one and 28-type blocks in another.

The variants printed above the rarities

Two kinds of variant are named on the publisher’s own product pages, and both sit outside the rarity ladder.

Parallel rare — named on every booster and starter deck page examined for this page, and described by the publisher as included in the product rather than as a rarity of its own.
Signature cards — certain boosters carry cards with a cast signature foil-stamped onto the card, and some carry serial-numbered Action Point cards issued at a low rate and in limited quantities. The publisher’s own note on the serial-numbered cards is that they are autographed by the cast, and that their inclusion in resale is undecided.

The distinction matters in the same way it does in every card game that prints treatments: a parallel rare is not a rarer card. It is the same card at the same rarity, printed differently. What the signature and serial-numbered cards add is a fact about the printing rather than about the card’s rarity.

What decides whether a card can go in your deck

This is the part of the card that is easy to overlook, and it is decisive. The rule manual sets out two requirements that come straight off the card number.

The source material code. Every card in a deck must share the same source material code — the first three letters of the card number. The manual’s own example is that a deck may include up to 4 cards with the number HTR-1-001, and all 50 cards must carry the code HTR.
The card number. No more than 4 copies of any cards with the same card number.

There is a further limit the manual states separately, and it is not the same rule as the copy limit: cards with SPECIAL COLOR and FINAL triggers are restricted to no more than four cards for each trigger type. So if two different cards both carry a SPECIAL trigger, their combined total in a deck cannot exceed four, even though they are different card numbers.

In other words, in UNION ARENA the deck is not assembled from a game-wide pool. It is assembled from one series, and that is why the first question a new player has to answer is which series to build rather than which card to find.

What this page does not claim

It does not state a pack size as a universal rule. The publisher states 8 cards per pack on the products examined here, but product configurations differ across the line.
It does not rank the rarities by scarcity beyond the publisher’s own type counts. Bandai lists how many types exist at each rarity, not how often each appears.
It does not print prices. CardSpicy quotes no prices and makes no valuation or investment recommendation.

Frequently asked questions

What are the card types in UNION ARENA?

Four: character cards, field cards, event cards and Action Point cards. Character and field cards are placed on the field, events are used and sidelined, and Action Point cards sit in a separate area as a resource.

What do the UNION ARENA rarity labels mean?

C is Common, U is Uncommon, R is Rare and SR is Super Rare. AP cards are listed as a separate category in the publisher’s type counts rather than as a rarity of the playable cards.

Why can I not mix series in one UNION ARENA deck?

Because the rule manual requires every card in a deck to share the same source material code, which is the first three letters of the card number. Cards from different series do not share that code.

How many copies of a card can I put in a deck?

Up to four cards with the same card number. Cards with SPECIAL COLOR or FINAL triggers have a separate limit of four cards combined for each trigger type.

Is a parallel rare card rarer than a normal one?

No. Parallel rare is a variant printing rather than a rarity. The card’s rarity is unchanged; only the printing differs.

Sources

Sources and scope

Bandai, the official UNION ARENA rule manual — the four card types and where each may be placed; the field layout including the Front Line, Energy Line, seven-card Life Area, AP Area, Deck Area, Sideline and Removal Area; Active and Resting; the labels on a character card including required energy, required action points, trait, series name, effect, trigger, activation energy, BP, rarity and card number; the deck construction rules including the fifty-card deck, the three Action Point cards, the shared source material code, the four-copy limit and the SPECIAL COLOR and FINAL trigger limits.
Bandai, the official UNION ARENA FAQ — the statement that energy generation is continuous and is not spent by playing a card, and the requirement that required energy be met in the matching colour.
Bandai, official UNION ARENA booster and starter deck product pages — the rarity labels C, U, R and SR; the separate AP category; the type counts quoted on this page; the note that parallel rare cards are included; and the description of foil-stamped signature cards and serial-numbered Action Point cards.
Scope note: only details published by Bandai, or printed on the cards, are stated as confirmed. No prices, no drop rates and no card count for the whole game are given.

Card pools, product contents and rules are set by the publisher and can change. Check Bandai’s own rules and product pages before acting on the basis of anything on this page.

Where to go next

The CardSpicy card index — every card we track, with its PSA 10 population and market history (195 cards).
The illustrator index — every artist behind those cards, card by card (110 artists).