Taladrador de corteza (Pith Driller)
Taladrador de corteza 

Cuando el Taladrador de corteza entre al campo de batalla, pon un contador -1/-1 sobre la criatura objetivo.
Texto de reglas (Oracle, inglés)
When this creature enters, put a -1/-1 counter on target creature.
Después de taladrar la corteza de Mirrodin, volcó su habilidad sobre los habitantes de la superficie.
Legalidad
Aclaraciones de reglas (en inglés)
2011-06-01
A card with Phyrexian mana symbols in its mana cost is each color that appears in that mana cost, regardless of how that cost may have been paid.
2011-06-01
To calculate the mana value of a card with Phyrexian mana symbols in its cost, count each Phyrexian mana symbol as 1.
2011-06-01
As you cast a spell or activate an activated ability with one or more Phyrexian mana symbols in its cost, you choose how to pay for each Phyrexian mana symbol at the same time you would choose modes or choose a value for X.
2011-06-01
If you're at 1 life or less, you can't pay 2 life.
2011-06-01
Phyrexian mana is not a new color. Players can't produce Phyrexian mana.
2011-06-01
Pith Driller's ability is mandatory. If it's the only creature on the battlefield when it enters, Pith Driller's ability will target itself.