Goblin Trapfinder

When Goblin Trapfinder dies, seek a creature
card with mana value 3 or less, and note it.
You get a Boon with
"The noted creature card costs {2} less to cast.
When it is on the battlefield, it has haste and
"at the beginning of your end step, sacrifice
this creature." When the noted creature card
is on the battlefield, this Boon ends."