Anything that takes out an opposing threat is nice, as are looting/card draw triggers or those which chain into further reanimation these are effects we need all the time anyway, and the more we can overlap them with this other core function of huge deadly attacker, the more consistent we will be
If the controller of Unyielding Gatekeeper's last ability controlled the target permanent at the time the ability began to resolve, the permanent will return to the battlefield tapped under that player's control, regardless of who its owner is
EX cards dominate the meta, but so do clever techs and support Trainers
By paying one green mana, you can sacrifice Implement of Ferocity to put a +1/+1 counter on target creature only at any time you could cast a sorcery
The Mono Black Control deck that surfaced at the start of the format could really benefit from a powerhouse like this, so hopefully this will be enough to change the landscape of Standard for the better
However, their usually lavish illustrations and design makes them highly desirable not to mention valuable to collectors