Those're pre-Revised artifacts. Back in the old days, "mono" meant an
artifact for which tapping was part of the activation cost; "poly" meant an
artifact which didn't tap when activated; "continuous" meant an artifact
that was like an enchantment.
>Oh, and can you use goblin grenade on your opponent's creatures?
If you meant to use your opponent's goblins as grenades, no. You can't
sacrifice permanents you don't control.
Followups to rec.games.trading-cards.magic.rules...
-- Jack
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