The List

Enchantment — Aura

Surge {U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Enchant creature
Enchanted creature doesn't untap during its controller's untap step.

Containment Membrane

Instant

Surge {1}{U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Tap target creature. It doesn't untap during its controller's next untap step.
Draw a card.

Grip of the Roil

Creature — Sphinx

Surge {2}{U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Flying

Jwar Isle Avenger

Sorcery

Surge {1}{R} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Boulder Salvo deals 4 damage to target creature.

Boulder Salvo

Surge {X}{R} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Fall of the Titans deals X damage to each of up to two targets.

Fall of the Titans

Creature — Goblin Warrior Ally

Surge {1}{R} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Haste
When this creature enters, if its surge cost was paid, other creatures you control get +1/+0 and gain haste until end of turn.

Reckless Bushwhacker

Oath of the Gatewatch Promos

Octopus

Surge {3}{U}{U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Return all nonland permanents to their owners' hands. If this spell's surge cost was paid, create an 8/8 blue Octopus creature token.

Crush of Tentacles

Surge {U}{U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
This spell can't be countered.
Counter target spell.

Overwhelming Denial

Creature — Dragon

Surge {3}{R}{R} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Flying
When this creature enters, if its surge cost was paid, it deals 3 damage to any target.

Tyrant of Valakut

Oath of the Gatewatch

Surge {2}{U} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Target player draws two cards.

Comparative Analysis

Surge {1}{R} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Menace (This creature can't be blocked except by two or more creatures.)