Opponents

There are 39 duelists in Yu-Gi-Oh! Forbidden Memories. Campaign mode is the story mode where you face opponents across a world map. As you defeat them, they become available in Free Duel — a separate mode where you can rematch any unlocked opponent to farm cards and Star Chips without story progression.

Several early opponents around Pharaoh's Palace are optional: Simon Muran, Jono, and the villagers can be skipped. After a scripted loss to Heishin, the World Tournament begins — a fixed sequence facing Rex Raptor, Weevil, Mai, Bandit Keith, Shadi, Yami Bakura, Pegasus, Isis, and Kaiba. Returning to Egypt, you defeat Mage Soldier at Pharaoh's Palace to unlock the five elemental shrines, each guarded by a mage and a High Mage (Ocean, Forest, Mountain, Desert, Meadow) in any order. Seto 2nd is an optional fight after defeating 2 mages — beating him removes Labyrinth Mage from the end sequence, turning the Final Seven into the Final Six. The endgame gauntlet then proceeds through Guardian Sebek, Guardian Neku, Heishin 2nd, Seto 3rd, DarkNite, and Nitemare with no saves or continues.

Duel Master K is a mirror match found in Free Duel — he uses an exact copy of your current deck. This makes him useful for early farming, especially if you need Thunder-type cards.

Each duelist has a drop table divided into three pools. Which pool you draw from depends entirely on your duel rank. The three pools are:

• S/A POW — available when you achieve S or A rank in the POW category (aggressive, quick duels)
• S/A TEC — available when you achieve S or A rank in the TEC category (technical, control-based duels)
• B/C/D — the default pool for any rank below A in either category

Each pool uses a weighted random system with a total pool size of 2048. Every card in a duelist's drop table is assigned a weight — for example, a common drop might have a weight of 64 (64/2048 ≈ 3.1% chance per roll), while a rare card like Meteor B. Dragon might have a weight of just 2 (2/2048 ≈ 0.1%). When you win a duel, the game rolls a number between 1 and 2048 and checks which card's weight range it lands in.

Drop modes (x1, x5, x15, x30, x100) multiply the number of card drops you receive from a single win. Higher drop modes drastically reduce the farming time needed.

POW (Power) and TEC (Technical) are the two duel ranking categories that determine which drop pool you access after a victory. During the duel, your actions affect a hidden score that determines your final rank:

POW ranks reward quick, aggressive duels — finish in few turns with effective attacks, minimal fusions, and high remaining LP. TEC ranks reward technical play using magic cards, trap activations, fusions, and defensive wins. Higher ranks (S/A) unlock better drop pools for most duelists.

For farming, A-TEC is often the sweet spot. S-TEC and A-TEC share identical drop pools for every duelist, but A-TEC is much faster to achieve — roughly 9 turns with 15 fusions, 4 effective attacks, 1 trap activation, and depleting your deck to 3 cards. S-TEC requires decking out the opponent, which takes 20–30 minutes per duel.

POW farming is best when you need monster drops and can OTK quickly. TEC farming is essential when the duelist's best drops are in their TEC pool — Pegasus (Megamorph, equips) and Shadi (Raigeki) are prime examples.

Forbidden Memories has a sophisticated AI system that varies significantly between duelists. Each duelist has configurable AI parameters — hand size, fusion length, spell probability, attack probability, and more — making each opponent feel distinct.

Unlike the player, AI opponents can hold more than 5 cards in their hand. Early duelists start with a hand size of 5, while endgame opponents go up to 20. For deck-out and Exodia checks, the game treats the AI as having a hand of 5 regardless of the actual hand size.

AI Decision States

The AI operates in three main decision states controlled by probability weights that differ per duelist:

• Find Best Combo — searches for the strongest fusion play from hand or on top of field monsters, limited by the duelist's Max Fusion Length (2–4). Combos are judged by the resulting monster's stats, with field bonuses applied. If the AI has Total Domination (its strongest monster beats the player's best), it's more likely to pursue combos.
• Improve Monster — activated when the AI is below its Low LP Threshold or by random chance. It loops over field monsters from weakest to strongest and attempts to improve them with hand combos. This is why weakened AI monsters often get fused into stronger ones.
• Set Magic — the AI falls back to setting spells, traps, or playing the strongest monster from hand if no combos are available.

If the AI Lacks Field Control (the player has a stronger monster), it prioritizes removal spells (Raigeki, Dark Hole, Crush Card), typing-specific destruction (Dragon Capture Jar, Warrior Elimination, etc.), and field spell manipulation before attempting combos.

Millennium Eye

A critical ability that sets certain duelists apart: Heishin, Pegasus, Heishin 2nd, Seto 3rd, DarkNite, and Nitemare can see your face-down cards. This means defensive strategies (face-down monsters, hidden traps) are less effective against them. They will only attack face-down monsters if they know they'll win the battle, and they factor your back row into their decisions.

AI Stats Per Duelist

Each duelist on their detail page shows their exact AI parameters: Hand Size, Max Fusion Length, Spell Probability, Attack Probability, Low LP Threshold, Critical Deck Size, and the probability distribution for all three decision states under both Total Domination and Lacks Domination conditions. Early duelists like Simon Muran have low stats (Hand Size 5, Fusion Length 2, Spell Prob 25%), while endgame opponents like Nitemare have maxed-out stats (Hand Size 20, Spell Prob 75%).

Different duelists excel at dropping different types of cards. Here are the most efficient farming targets based on community consensus:

Each duelist has a dedicated page with their exact drop tables and weights, so you can see the precise probability for every card at every rank.

The Drop Rate Table below the duelist grid is a complete matrix showing every card that drops from each duelist. Each row is a duelist, and the cards are organized by rank group (S/A POW, S/A TEC, B/C/D). Hover over a card to see its drop weight and exact probability.

The Duelists Filter helps you find which opponents drop specific cards. You can filter by card type (Monster, Equip, Magic, Trap), by group (Dragons, High ATK, etc.), or by searching for a card name directly. The filter adapts in real-time — type 'Meteor B. Dragon' and it highlights every duelist that can drop it, at which rank, and with what probability.

You can also filter by duelist group — each duelist belongs to campaign chapters and pre-defined groups. Use the tabs at the top to switch between viewing duelists by DECK (their deck composition), S/A POW drops, S/A TEC drops, and B/C/D drops.