Athreos Shroud-Veiled changes properties of cards

[[Athreos, Shroud-Veiled]] The coin does change the properties of the given card. Altered creatures remain the properties and if a creature has abilities that work from the graveyard they are active for the player that stole the creature.

Start by locating the Athreos, Shroud-Veiled card implementation and the rules handling for its coin effect and stolen creatures. Reproduce the reported cases, then verify that the affected card properties persist and that applicable graveyard abilities work for the player who controls the creature.

Written by the indexing model from the issue text.