edhseer Commander synergy, explained
Instant
Mana cost: {3}{U}
The owner of target nonland permanent puts it on their choice of the top or bottom of their library.
on-cast —
Counter target noncreature spell.
on-cast —
Causes: you face a dilemma, an artifact leaves the battlefield, a battle leaves the battlefield, a creature leaves the battlefield, an enchantment leaves the battlefield, a planeswalker leaves the battlefield, counter an artifact, counter a battle, counter an enchantment, counter an instant, counter a planeswalker, counter a sorcery.
Cares about: nothing.
you face a dilemma — 739 cards in the game can cause this (Riverwalk Technique is one).
When Riverwalk Technique poses a dilemma:
an instant is cast — 3,931 cards in the game can cause this (Riverwalk Technique is one).
When Riverwalk Technique is cast:
427 other cards care about it too. These are the ones with the most connections.
a nontoken creature leaves the battlefield — 4,133 cards in the game can cause this (Riverwalk Technique is one).
3 other cards care about it too. These are the ones with the most connections.
a creature leaves the battlefield — 4,238 cards in the game can cause this (Riverwalk Technique is one).
When a creature leaves the battlefield thanks to Riverwalk Technique:
25 other cards care about it too. These are the ones with the most connections.
anything is cast — 31,128 cards in the game can cause this (Riverwalk Technique is one).
When Riverwalk Technique is cast:
5 other cards care about it too. These are the ones with the most connections.