Argent Dais's second ability triggers whenever two or more creatures attack, not just when you attack with two or more creatures.
2024-06-07
If the target nonland permanent is illegal as Argent Dais's last ability tries to resolve, it won't resolve and none of its effects will happen. No player will draw cards.
This artifact enters with two oil counters on it.
Whenever two or more creatures attack, put an oil counter on this artifact.
, , Remove two oil counters from this artifact: Exile another target nonland permanent. Its controller draws two cards.
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