Riku of Two Reflections Since Riku of Two Reflectionss ability triggers when a creature enters, you can use cards like Thassa, Deep-Dwelling and Essence Flux to generate many copies of one card
I suspect there's gonna be a stampede for 'em
Then if it has three or more +1/+1 counters on it, sacrifice this Aura
We might have expected a few changes, but seven bans like this are unprecedented
If one of those creatures can't attack its owner that turn due to a spell or ability (such as Chronomantic Escape), you may have it attack another player, attack a planeswalker an opponent controls, attack a battle an opponent protects, or not attack at all
This card was upshifted to Mythic after its initial printing in Ravnica: City of Guilds, which means that it still holds a lot of value