Artefacto
Al comienzo de tu mantenimiento, destruye el permanente objetivo que no sea tierra con el menor coste de maná convertido entre los permanentes en juego que no sean tierra. (Si dos o más permanentes empatan por el menor coste, elige el objetivo entre ellos.)
Most tokens have a mana value of 0. A token that's a copy of another permanent or card has a mana value equal to that permanent or card's mana value.
If the targeted permanent doesn't have the lowest mana value when the ability resolves, the ability doesn't resolve and the permanent isn't destroyed.
If the lowest mana value is 3, Culling Scales can destroy itself.
You choose the target. If there's more than one nonland permanent tied for lowest mana value, you choose which one to target.