Ozwin Ophi, The Sentinel

Vigilance, lifelink
Whenever a creature blocks or becomes blocked
by Ozwin Ophi, you may pay {w/u}{w/u}. If you do, detain it and remove it from combat.
Whenever a creature an opponent controls attacks you or a planeswalker you control and
isn't blocked, you may pay {r/w}{r/w}. If you do,
Ozwin Ophi deals 3 damage to that creature.