Darkthicket Wolf‘s activated ability has a restriction on it preventing the ability from being activated more than once per turn. This restriction applies regardless of who controls it when the ability is played.

For example, if Darkthicket Wolf’s ability is activated by Player A and then this Darkthicket Wolf is targeted by Traitorous Blood played by Player B, Player B will not be able to activate Darkthicket Wolf’s ability. It does not matter that Player B has not activated this ability yet that turn.