Mila's Turnwheel (ミラの歯車, Mira no Haguruma lit. Mila's Gear) is a special item introduced in Fire Emblem Echoes: Shadows of Valentia.
Mila's Turnwheel is a relic tied to the goddess, Mila and has the ability to grant visions of the past and future to the user. Silque, as a member of the Novis Priory, had a Mila's Turnwheel of her own which she was tasked with delivering to Alm. While she is captured by thieves, Alm makes a timely rescue and Silque gives the Turnwheel to Alm to use on his journey. Celica also has a Turnwheel in her possession which she acquired during her time at Novis Priory. Though functionable, both turnwheels have lost some of its power, due to several pieces of it being missing and scattered across Valentia. Both Turnwheels are revealed to be the keys to unlock the doors at Duma Temple into Duma's lair.
During a battle, Mila's Turnwheel allows the player to rewind the current map as far back as the player desires. The reversal plays back action-by-action, allowing the player to choose which turn or even which unit action choice to restart from. This allows the player to retry an attack that did not get the results the player was looking for or revive ally characters and restart from a desired point on the map, rather than having to restart from the beginning of a map. While attacks can be replayed for a different outcome, any stat gains from a Level up that is undone by Mila's Turnwheel will occur the same way when the unit re-levels up again on the map. While Mila's Turnwheel can be used to return to a certain point in the battle, it cannot be used in the case where Alm or Celica dies, which results in an automatic Game Over and will require the player to restart the battle from the very beginning. Also, there seems to be a glitch which makes your game crash if you use Mila's Turnwheel during turn 1 of a battle (except in randomly generated battles).
When initially acquired, both Turnwheels have a maximum charge of three uses per battle. Scattered throughout the storyline in various dungeons and important fort liberations are Gears. Each gear acquired grants a permanent additional usage of both Turnwheels, maxing out to 12 uses should all 9 hidden gears be found. The Turnwheel usage resets to maximum at the end of all chapter battles. In a dungeon, Mila's Turnwheel does not reset upon completing a battle. Instead, the player must find the Statue of Mila inside of the dungeon and offer any Wine drink.
Items called Memory Prisms make use of the Turnwheel as well, with these fragments showing past experiences of characters and expands on their lives before the events of the game.
Mila's Turnwheel can also summon temporary allies to the field by using amiibo figures. Alm or Celica must pay 10 HP in order to summon these illusory or monster units. Allies summoned by the Turnwheel cannot be controlled by the player and will only exist on the map for a single turn. Using a Marth, Roy, Ike, Robin, Lucina, or Corrin amiibo will summon an Illusory Hero version of their character. Alm and Celica's amiibo summon illusory versions of themselves. Their versions have varying stats, depending on the stat data saved onto their amiibo when registering them. All other amiibo figures or cards will summon an allied monster instead.
- According to an interview with the developers, the turnwheel is meant to resemble an Antikythera Wheel.
- Though Mila's Turnwheel explains in the story that it grants visions of the past and future, a cleric explaining the cogs to upgrade the Turnwheel would actually explain that it rewinds time, which breaks the lore.