Bident of Thassa {2}{U}{U}

Legendary Enchantment Artifact

Whenever a creature you control deals combat damage to a player, you may draw a card.

{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Only Kiora would dare steal the weapon of a god. Only Kiora could have succeeded.

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Prints	USD	EUR	TIX
The Lost Caverns of Ixalan Commander	$0.99	€1.11
Starter Commander Decks	$0.91	€1.93
The Brothers' War Commander	$1.09	€1.33	0.08
Masters 25	$3.74	€1.42	0.03
Commander 2015	$1.63	€1.26
Magic Online Promos			0.03
Theros	$3.37	€1.18	0.02
Theros Promos	✶ $1.27
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The controller of each attacking creature still chooses which player or planeswalker that creature attacks. (2018-03-16)

If a creature can't attack for any reason (such as being tapped or having come under that player's control that turn), then it doesn't attack. If there's a cost associated with having a creature attack, the player isn't forced to pay that cost, so it doesn't have to attack in that case either. (2018-03-16)