Snow-Covered Mountain

Wyll, Blade of Frontiers

If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll.
Whenever you roll one or more dice, put a +1/+1 counter on Wyll, Blade of Frontiers.
Choose a Background (You can have a Background as a second commander.)

Faceless Haven

{T}: Add {C}.
{S}{S}{S}: Faceless Haven becomes a 4/3 creature with vigilance and all creature types until end of turn. It's still a land. ({S} can be paid with one mana from a snow source.)

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Snow-Covered Island

Brazen Dwarf

Whenever you roll one or more dice, Brazen Dwarf deals 1 damage to each opponent.

Petty Theft

Return target nonland permanent an opponent controls to its owner's hand.

Brazen Borrower

Flash
Flying
Brazen Borrower can block only creatures with flying.

Brazen Borrower // Petty Theft

Fire Prophecy

Fire Prophecy deals 3 damage to target creature. You may put a card from your hand on the bottom of your library. If you do, draw a card.

Volatile Fjord

({T}: Add {U} or {R}.)
Volatile Fjord enters tapped.

Lavaglide Pathway

Riverglide Pathway

Riverglide Pathway // Lavaglide Pathway

Delina, Wild Mage

Whenever Delina, Wild Mage attacks, choose target creature you control, then roll a d20.
1—14 | Create a tapped and attacking token that's a copy of that creature, except it's not legendary and it has "At end of combat, exile this creature."
15—20 | Create one of those tokens. You may roll again.

Counterspell

Frost Bite

Frost Bite deals 2 damage to target creature or planeswalker. If you control three or more snow permanents, it deals 3 damage instead.

Pixie Guide

Flying
Grant an Advantage — If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll.

Mazemind Tome

{T}, Put a page counter on Mazemind Tome: Scry 1.
{2}, {T}, Put a page counter on Mazemind Tome: Draw a card.
When there are four or more page counters on Mazemind Tome, exile it. If you do, you gain 4 life.

Barbarian Class

(Gain the next level as a sorcery to add its ability.)
If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll.
{1}{R}: Level 2
Whenever you roll one or more dice, target creature you control gets +2/+0 and gains menace until end of turn.
{2}{R}: Level 3
Creatures you control have haste.

Stomp

Damage can't be prevented this turn. Stomp deals 2 damage to any target.

Bonecrusher Giant

Whenever Bonecrusher Giant becomes the target of a spell, Bonecrusher Giant deals 2 damage to that spell's controller.

Bonecrusher Giant // Stomp

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.