Whenever you spend at least five mana to cast a spell, untap Opal-Eye Runeweaver.
{T}: Untap another target permanent not named Opal-Eye Runeweaver. Activate only as a sorcery.

When Opulent Roughrider enters or leaves the battlefield, surveil 1, then you may reveal the top card of your library. If that card has the same name as a permanent you control or a card in your graveyard, put it into your hand.
Wander {4}{U}{U}

Exile target creature or planeswalker. Its controller loses 2 life.

Counter target spell. That spell's controller reveals their hand. Choose any number of nonland cards from it. That player puts those cards on the bottom of their library in any order, then draws that many cards.

At the beginning of combat on your turn, if you've spent at least five mana to cast spells this turn, Peaktop Predator deals 2 damage to target player or planeswalker.

When Pensive Caldera enters, you may discard a card. If you do, draw a card.
{T}: Add {R}. Spend this mana only to cast artifact, instant, or sorcery spells.

Flash
When Permafrost Lynx enters, target creature you don't control doesn't untap during its controller's next untap step.

Defender
{1}{U}: Permafrost Sentry becomes a copy of target Ruin you control.

Flash
When Permafrost Tiger enters, you may have it fight target creature that entered this turn.

Deathtouch
When Phyto's Offshoot enters, you may exile any number of permanent cards from your graveyard. When you do, target opponent reveals that many cards from their hand. You choose one of them. That player discards that card.

Whenever one or more cards leave your graveyard, put a +1/+1 counter on Phyto, Caverns Scourge, then each opponent loses life equal to half its power, rounded up. This ability triggers only once each turn.
{X}{X}{B}{G}, Exile Phyto, Caverns Scourge from your graveyard: Return X other target permanent cards from your graveyard to your hand.

As an additional cost to cast spells during an opponent's turn, you may pay {U} and reveal Promethean Jaxl from your hand. If you do, you get a lurk counter.
Flash
Promethean Jaxl enters tapped.
When Promethean Jaxl enters, you draw a card for each lurk counter you have, then you lose all lurk counters.

Enchant creature
Enchanted creature gets +1/+1 and can't block.
Wander {1}{B}

Flash
This spell costs {1} less to cast for each permanent with flash you control and each instant card in your graveyard.
Ward {2}

Counter target spell. Create an X/X blue and black Fish creature token, where X is the total number of permanents with flash you control and the number of instant cards in your graveyard.

Target creature you control gets +1/+1 until end of turn. Prevent all combat damage that other creatures would deal this turn.

Trample, ward {3}
Other Yetis you control get +1/+1.
At the beginning of combat on your turn, if you've spent at least five mana to cast spells this turn, create a 3/3 green Yeti creature token with trample.

Menace
Creatures you control get +1/+0 if you've cast a spell that targeted Rathomar Forerunner this turn.

Whenever you cast a spell that targets Rathomar Harrier, choose one. If Rathomar Harrier is attacking, choose both instead.
• Tap target creature you don't control.
• Create a 2/2 green Wolf creature token.

Whenever you cast a spell that targets Rathomar Herder, choose one. If Rathomar Herder is attacking, you may choose both instead.
• Create a 1/1 white Human creature token.
• Creatures you control get +1/+0 until end of turn.

Haste
Whenever you cast a spell that targets Rathomar Raider, target creature can't block this turn.

When Reaching Remnant enters, it deals 4 damage to target creature with flying you don't control.
Spellcharge 3

Return target artifact or creature card from your graveyard to the battlefield.
Flashback—{3}{B}, Sacrifice a creature.

Whenever Recurring Visions enters or you cast a spell which had its flashback cost paid, surveil 3.

Mill a card. Put a +1/+1 counter on up to one target creature. Exile up to one target card from a graveyard. You gain 1 life.
Flashback {1}{G}