| 5/1/2008 |
If the permanent is already untapped, you can't activate its  ability. That's because you can't pay the "Untap this permanent" cost. |
| 5/1/2008 |
If a creature with an ability hasn't been under your control since your most recent turn began, you can't activate that ability, unless the creature has haste. |
| 5/1/2008 |
When you activate an ability, you untap the creature with that ability as a cost. The untap can't be responded to. (The actual ability can be responded to, of course.) |
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