Text (SM): 2/1, Flying. ; ~this~ can't have counters placed on it.
Any effect that would add a counter to this creature simply doesn't do so. The effect still does whatever else it would do. [Shadowmoor FAQ 2008/04/21]
If a Wither damage is dealt to this, the damage simply does nothing. It does not get treated as normal damage and does not add counters. [Shadowmoor FAQ 2008/04/21]
You can't pay a cost that includes putting a counter on this. For example, you can't play Scarscale Ritual by putting a counter on this. [Shadowmoor FAQ 2008/04/21]
