Two-Headed Sliver

All Sliver creatures have menace. (They can't be blocked except by two or more creatures.)

Night Market Guard

This creature can block an additional creature each combat.

Mountain

Thriving Bluff

This land enters tapped. As it enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Twinflame Tyrant

Flying
If a source you control would deal damage to an opponent or a permanent an opponent controls, it deals double that damage instead.

Three-Headed Goblin

Triple strike (This creature deals first-strike, regular, and last-strike combat damage.)

Frost Giant

Rampage 2 (Whenever this creature becomes blocked, it gets +2/+2 until end of turn for each creature blocking it beyond the first.)

Twice the Rage

Target creature gains double strike until end of turn. (Then exile this card. You may cast the creature later from exile.)

Two-Headed Hunter

Menace (This creature can't be blocked except by two or more creatures.)

Two-Headed Hunter // Twice the Rage

Two-Headed Giant of Foriys

Trample
This creature can block an additional creature each combat.

Two-Headed Giant

Whenever this creature attacks, flip two coins. If both coins come up heads, this creature gains double strike until end of turn. If both coins come up tails, this creature gains menace until end of turn.

Smoldering Spires

This land enters tapped.
When this land enters, target creature can't block this turn.
{T}: Add {R}.

Foriysian Totem

{T}: Add {R}.
{4}{R}: This artifact becomes a 4/4 red Giant artifact creature with trample until end of turn.
As long as this artifact is a creature, it can block an additional creature each combat.

Jawbone Skulkin

{2}: Target red creature gains haste until end of turn.

Gorgon's Head

Equipped creature has deathtouch.
Equip {2}

Two-Headed Zombie

Two-Headed Hellkite

Flying, menace, haste
Whenever this creature attacks, draw two cards.

Teetering Peaks

This land enters tapped.
When this land enters, target creature gets +2/+0 until end of turn.
{T}: Add {R}.

Ogre-Head Helm

Equipped creature gets +2/+2.
Whenever this creature or equipped creature deals combat damage to a player, you may sacrifice it. If you do, discard your hand, then draw three cards.
Reconfigure {3} ({3}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Double Trouble

Double the power of each creature you control until end of turn.

Two-Headed Cerberus

Double strike (This creature deals both first-strike and regular combat damage.)

Two-Headed Dragon

Flying
Menace (This creature can't be blocked except by two or more creatures.)
This creature can block an additional creature each combat.
{1}{R}: This creature gets +2/+0 until end of turn.