Tawnos's Coffin

You may choose not to untap this artifact during your untap step.
{3}, {T}: Exile target creature and all Auras attached to it. Note the number and kind of counters that were on that creature. When this artifact leaves the battlefield or becomes untapped, return that exiled card to the battlefield under its owner's control tapped with the noted number and kind of counters on it. If you do, return the other exiled cards to the battlefield under their owner's control attached to that permanent.

Skullbriar, the Walking Grave

Haste
Whenever Skullbriar deals combat damage to a player, put a +1/+1 counter on it.
Counters remain on Skullbriar as it moves to any zone other than a player's hand or library.