Ulrich Mercury

Unblockable, Merc cannot be countered.
Merc has +2/+0 when attacking. If a Indestructible creature would be brought to zero life or less by Merc, put it into owner's graveyard and put a +1/+1 counter on Merc for each toughness the creature had.
If Merc is in a graveyard at beginning of your upkeep, return to the battlefield tapped.