Valakut, the Molten Pinnacle

Valakut, the Molten Pinnacle enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have Valakut, the Molten Pinnacle deal 3 damage to any target.
{T}: Add {R}.

Strangle

Strangle deals 3 damage to target creature or planeswalker.

Smelt-Ward Minotaur

Whenever you cast an instant or sorcery spell, target creature an opponent controls can't block this turn.

Minotaur Sureshot

Reach (This creature can block creatures with flying.)
{1}{R}: Minotaur Sureshot gets +1/+0 until end of turn.

Sardian Cliffstomper

As long as it's your turn and you control four or more Mountains, Sardian Cliffstomper gets +X/+0, where X is the number of Mountains you control.

Minotaur

Thundering Rebuke

Thundering Rebuke deals 4 damage to target creature or planeswalker.

Sethron, Hurloon General

Whenever Sethron, Hurloon General or another nontoken Minotaur you control enters, create a 2/3 red Minotaur creature token.
{2}{B/R}: Minotaurs you control get +1/+0 and gain menace and haste until end of turn. ({B/R} can be paid with either {B} or {R}.)

Warlord's Fury

Creatures you control gain first strike until end of turn.
Draw a card.

Minotaur Skullcleaver

Haste
When Minotaur Skullcleaver enters, it gets +2/+0 until end of turn.

Soul Sear

Soul Sear deals 5 damage to target creature or planeswalker. That permanent loses indestructible until end of turn.

Mountain

Reckless Impulse

Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Neheb, Dreadhorde Champion

Trample
Whenever Neheb, Dreadhorde Champion deals combat damage to a player or planeswalker, you may discard any number of cards. If you do, draw that many cards and add that much {R}. Until end of turn, you don't lose this mana as steps and phases end.