Sir Mason, The Short

Indestructible, First Strike, Trample, Vigilance
When this card enters the battlefield, create Witherrune, a legendary equipment artifact that
has "Equip {5} and Equipped creature has +2+2,
double strike, deathtouch and lifelink." Then
attach it to Sir Mason.
Whenever a knight attacks, gain X life, Draw X
cards, and deal X damage to target creature where
X is that creature's power.
"Its just a prank, bro." -Sir Mason