Since Beta 48.1, Resurrection sends a copy of 2 random non-Token monsters from your dustpile to your hand. As such, if you only have 1 non-Token card in your dustpile you will get 2 new ones of it.
Then, if your HP is at 15 or lower, a Lost Soul will also be added to your hand, as long as there's room. This Lost Soul will be the next one in the cycle. Check the Lost Soul image for the order they are given. It matches with DT's Passive as well as Will to Fight (since the same update) and Another Chance. Universal among all 'Lost Soul Generators', Thrashing Machine cannot be obtained. If any of the 3 spells is used by a non-DT player and they obtain a Lost Soul, it will instead be a random one.
Be sure about when to use it to not miss out on the amount of cards you can receive while also not clogging your hand (though Preservation allows you to work around it). If your HP is below 16, you will receive 3 cards, with the Lost Soul last. So you should use this when you have at most 5 cards in your hand, this included.