Gnarlhorn (rare) - Skinwalkers

I was thinking about his S2 War Drum.
It places debuff Provoke on all enemies for 1 turn. As written, it's 100% chance.
What about, for arena, a Gnarlhorn with Accuracy and Speed (or a Speed buffer as Seeker) and maybe lot of HP and/or Defence?
Acting before enemy champions, places Provoke on them.

Basically all enemy party skip first 'regular turn', attacking Gnarlhorn (he 'just' has to keep alive for that turn).
If he'll survive, on his second turn can cast Determined to grant an Unkillable buff on him.

Do you guys think it could work?
Thank you!