Mountain

Hazoret's Monument

Red creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, you may discard a card. If you do, draw a card.

Charming Scoundrel

Haste
When Charming Scoundrel enters, choose one —
• Discard a card, then draw a card.
• Create a Treasure token.
• Create a Wicked Role token attached to target creature you control.

Norin, Swift Survivalist

Norin, Swift Survivalist can't block.
Whenever a creature you control becomes blocked, you may exile it. You may play that card from exile this turn.

Sunspine Lynx

Players can't gain life.
Damage can't be prevented.
When Sunspine Lynx enters, it deals damage to each player equal to the number of nonbasic lands that player controls.

Guild Artisan

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, you create two Treasure tokens." (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Witty Roastmaster

Alliance — Whenever another creature you control enters, Witty Roastmaster deals 1 damage to each opponent.

Iraxxa, Empress of Mars

Trample
Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Paradox — Whenever you cast a spell from anywhere other than your hand, create a 2/2 red Alien Warrior creature token.

Invasion Plans

All creatures block each combat if able.
The attacking player chooses how each creature blocks each combat.

Imperial Recruiter

When Imperial Recruiter enters, search your library for a creature card with power 2 or less, reveal it, put it into your hand, then shuffle.

Fanatic of Mogis

When Fanatic of Mogis enters, it deals damage to each opponent equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Wily Goblin

When Wily Goblin enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")