When summoned, the AoD allows you to copy any monster on the board and place it on your board, including enemy monsters. (So if you copy an ally monster, you have 2 of the same.)
This works as a better version of Echo Fish, as after you copy a powerful monster, you can use cards like Break or Doggo to put it back in your hand and activate its Magic (if it has one). You can also use those on the AoD himself to copy more monsters.
When the AoD dies, the empty spaces on your board will be filled with a random Lost Soul. These are all weaker versions of the original monster with lower stats, lower cost and a weaker ability, all of which are Dust. You can't get 2 of the same Lost Soul from AoD's Dust.
The AoD is a Determination card, and as with all cards of this rarity, it can't be Silenced and in Ranked, it's banned to have more than 1 in your deck since Beta 13.1. It can also only be obtained through:
- Normal Packs (with 1/500 chance);
- Final Packs (which you get 1 of at LV 200);
- Special Events (on Twitter or Facebook);
- Crafting with DT Fragments. You can get DT Fragments by:
- Logging in 28 times in a month;
- Reaching Ruby IV or higher in Classic. (Ruby = 1; Diamond = 1; Legend = 2)
- God of Hyperdeath (by Darky)
- Cry Baby of Death (by Moonlightring)
- Undyne, Asgore, and Alphys's Lost Soul sprite are different then in the game.
- Summons an exact copy of a monster, just like Cloning.
- Before the introduction of the Generated Rarity in Beta 30.0, Lost Souls 1-5 were Legendary (and Lost Soul 6 Epic), the same as their normal versions. Because of this, they would play the same Theme as them when replayed.
- With Beta 30.0 also changing that Themes play when a monster gets summoned through any means rather than just your hand, all Lost Souls lost their Theme. Otherwise, up to 4 Themes would play at once which is extremely loud.