Fusions

Fusion is the core engine of Forbidden Memories: almost all powerful monsters are created through it, which is why your duel rank rewards initiating fusions promptly (see Rules §13).

1. What Combines

When two cards meet — whether two raised in hand or one played onto the field — the game checks them in this order:

1. Fusion. The pair is looked up in the fusion table.

2. Equip. If one card is an Equip and the other is a monster, the Equip boosts the monster’s stats.

3. Ritual (§5.7): not a combination; it is activated directly from the field.

4. Failure. If neither applies: when only one of the two cards is a monster,

If the pair exists in the fusion table, the two cards combine into the result monster, placed face-up with the result’s stats.

The catalog contains 25,146 fusions, of which 15 exist solely due to the game’s index overflow reading bug.

2. Fusing in Hand vs. Fusing on Field

• Two cards in hand: raise both using up on the d-pad, and the game combines them in the numerical order you selected.
• One card onto the field: play the card directly on top of a monster already on your field.

The placement order is field card first → hand 1 → hand 2…; it does not “fuse the hand first.”

Combining on the field follows the same recipe table, but the result keeps the field zone, prompts you again for battle position, and counts as a field fusion rather than an initiated hand fusion for rank scoring.

3. Chains of Three or More Cards

A chain of three or more raised cards is processed pairwise: the first two cards, then that result with the third, and so on. Each step can succeed or fail under the same rules, and whichever card survives the full sequence is placed on the field.

In short: a chain is a sequence of two-card fusions. If a step fails, the chain continues using that step’s surviving card. An Equip can be included in the chain: if a fusion result equips an item, that monster enters the next step as material with the stat bonus already applied.

The game’s planner evaluates subsets of up to five cards across the five field zones, creating up to 1625 non-empty paths.

4. What Happens on Fusion Failure

• If only one of the two cards is a monster, the monster remains and the other card is discarded.
• If both are monsters (or neither is), the card played first is discarded and the second card remains.

In practice: a failed two-monster fusion costs you the first card; a misplayed Equip costs you the Equip card.

5. “Generic” Type Patterns

This section describes an observed pattern across game data, not an explicit hardcoded engine rule. The engine has no generic “Type + Type = X” formula: it looks up a concrete table of 25,146 specific recipes. However, because hundreds of recipes share the same input type pair and output, new players frequently encounter the same resulting monsters.

Across the catalog’s 25,146 fusion recipes:

• 24,968 are standard monster fusions (monster + monster → monster).
• 24,955 of those satisfy the rule: “the result has higher ATK than either material.”
• 13 do not satisfy it (these are the game’s 13 anomalies, 4 of which yield Cocoon of Evolution with 0 ATK).
• 175 recipes involve at least one non-monster material, and 161 yield a non-monster result (123 Magic, 26 Ritual, 12 Trap).

This rule is also stated in the official guidebook: a standard successful fusion produces a monster stronger than its components.

Most Frequent Patterns with Real IDs

The results fed by the largest number of recipes are Nekogal #2 (1,200 recipes), Mystical Sand (1,174), and Cyber Soldier (1,008); this is why they constantly appear when beginners experiment with random fusions.

6. The 15 “Overflow” Fusions

Fifteen entries in the table are not intentional game recipes: they are corrupt table lookups caused by an index overflow. The catalog isolates them, and they should not appear in the fusion helper as playable recipes.

All fifteen overflow recipes with their IDs:

Of these fifteen, 13 make up the exact exceptions to the ATK progression rule (four produce Cocoon of Evolution, which has 0 ATK). The other two (id 45 + id 170 and id 61 + id 144, both yielding Witty Phantom) do increase ATK and therefore do not appear among the 13 exceptions.

7. Equips in Fusion Chains

An Equip card is not a fusion: it is evaluated as step two of card interactions. The game checks the equip table and, if the pair is compatible, increases the monster’s ATK and DEF while consuming the Equip card.

In the game: +500 per equip tier, and Megamorph (two tiers) adds +1000.

The equip table contains 4,041 valid pairs (34 Equips × compatible monsters): Megamorph fits 621 monsters, and Legendary Sword fits 63.

An Equip played onto an empty monster zone is rejected.

8. Rituals

A Ritual does not fuse: it activates, tributes three monsters from your field, and summons the ritual monster. If any required materials are missing, the Ritual card is consumed without summoning anything.

The catalog contains 24 Rituals, each specifying three tributes and the result.

Disc examples:

• Black Luster Ritual = Beaver Warrior + Gaia the Fierce Knight + Kuriboh → Black Luster Soldier
• Ultimate Dragon = three Blue-eyes White Dragon → Blue-eyes Ultimate Dragon
• Gate Guardian Ritual = Sanga of the Thunder + Kazejin + Suijin → Gate Guardian
• Dark Magic Ritual → Magician of Black Chaos

A surprising detail: 22 Ritual monsters are unobtainable. They exist solely during duels when summoned; they cannot be stored in your trunk or purchased.

9. In-Game Fusion Helper

The game includes a turn planner that, when requesting help, returns up to three distinct viable fusion paths.

This planner does not evaluate the overall duel outcome: it ignores Raigeki, Rituals, the entire battle phase, and set Traps.

For this reason, the helper serves as a combination map, not a guaranteed duel solution.