Jester, Harbinger of the Fool

Reach, lifelink
Activated abilities that require a permanent to
pay {1} is replaced with {p/c}.
Whenever a creature attacks you this turn, you
lose 1 life. If Jester blocks a creature this turn, it
assigns combat damage equal to its toughness
rather than its power.
{3}{u}{r}{r}: Deals X damage to target creature
or planeswalker, where X is equal to the life
you lost this turn.