Duels are a mode of play available in all Acts of Shadow Fight 2. They are unlocked after the player defeats two bodyguards of a demon. Internet connection is required to play duels. Duels are very much like a single stage of challenge. They have a maximum of three rounds on each try, two of which must be won by the player to count as a victory (unless otherwise stated by the rules). The player will face several unnamed ninja with random equipment and different rules. The rounds are always 99 seconds in duration, unless otherwise decided by the duel's rules, before which the player must defeat the opponent or it will count as a loss (unless otherwise stated by the duel's rules). When a duel is lost the player can choose to play it again. If the player wins the duel, the mode gets locked and cannot be played again in any province for four hours. Duels run on a four clock. After every four hours, if the person does not win a duel in any Act, a new opponent and challenge is presented. Duels usually notify the new challenges after four hours; however, if the duel was not locked before it was refreshed, it will not push a notification.
Duels in Act I have a rule of giving random equipment to the players. Duels in other Acts have fully random rules where the player is either put at a disadvantage, the opponent is given superiority or the battle rules are altered along with random equipment. The player never gets to choose their equipment in a duel. The difficulty remains constant for Duels, with the normal state having Normal Difficulty, while Eclipse having Hard Difficulty. The reward of winning the duel in Act I increases from when it is unlocked by leveling up until its highest when the player reaches level 6. The reafter it remains the same for the rest of the games. The XP awarded by winning a duel is greater than that offered by winning Survival, but still too small to contribute adequately to leveling up.
Winning a Duel will reward the player with a amount of Coins and Shadow Orbs. The number of prizes depends on the player's level.
- Challenger fights happen at duel's background. Even when the duel itself have not been unlocked.
- Defeating the second bodyguard not only unlocks the duel in that Act, but also of the previously completed Acts even if they were on the four hour temporary lock. After winning the now unlocked duel, the lock is reinstated for the next four hours.
- The Interlude and Act VII does not require the defeat of two bodyguards to unlock the Duel of that province.
- No enchantments are present during duels for both the player and the enemy, due to the fact that players are given random equipment instead of their equipment of choice.
- Before the Ascension removed, Duel rewarded 2 ascension tickets as the prize.