Hushwing Gryff

If Hushwing Gryff and another creature enter the battlefield at the same time, neither creature entering the battlefield will cause triggered abilities to trigger.

Look at the permanent as it exists on the battlefield, taking into account continuous effects, to determine whether any triggered abilities will trigger. For example, if you control March of the Machines, which says, in part, “Each noncreature artifact is an artifact creature,” each artifact will be a creature at the time it enters the battlefield and will not cause triggered abilities to trigger.

Triggered abilities use the word “when,” “whenever,” or “at.” They’re often written as “[Trigger condition], [effect].”

Abilities that create replacement effects, such as a permanent entering the battlefield tapped or with counters on it, are unaffected.