Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Metallurgic Summonings

Whenever you cast an instant or sorcery spell, create an X/X colorless Construct artifact creature token, where X is that spell's mana value.
{3}{U}{U}, Exile Metallurgic Summonings: Return all instant and sorcery cards from your graveyard to your hand. Activate only if you control six or more artifacts.

Peregrine Drake

Flying
When Peregrine Drake enters, untap up to five lands.

Aggravated Assault

{3}{R}{R}: Untap all creatures you control. After this main phase, there is an additional combat phase followed by an additional main phase. Activate only as a sorcery.

Cathars' Crusade

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

Narset, Enlightened Master

First strike, hexproof
Whenever Narset, Enlightened Master attacks, exile the top four cards of your library. Until end of turn, you may cast noncreature spells from among those cards without paying their mana costs.

Anointed Procession

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Young Pyromancer

Whenever you cast an instant or sorcery spell, create a 1/1 red Elemental creature token.

Sword of Feast and Famine

Equipped creature gets +2/+2 and has protection from black and from green.
Whenever equipped creature deals combat damage to a player, that player discards a card and you untap all lands you control.
Equip {2}

Land Tax

At the beginning of your upkeep, if an opponent controls more lands than you, you may search your library for up to three basic land cards, reveal them, put them into your hand, then shuffle.

Iroas, God of Victory

Indestructible
As long as your devotion to red and white is less than seven, Iroas isn't a creature.
Creatures you control have menace.
Prevent all damage that would be dealt to attacking creatures you control.

Intruder Alarm

Creatures don't untap during their controllers' untap steps.
Whenever a creature enters, untap all creatures.

True Conviction

Creatures you control have double strike and lifelink.

Mana Echoes

Whenever a creature enters, you may add an amount of {C} equal to the number of creatures you control that share a creature type with it.

Dramatic Reversal

Untap all nonland permanents you control.

Isochron Scepter

Imprint — When Isochron Scepter enters, you may exile an instant card with mana value 2 or less from your hand.
{2}, {T}: You may copy the exiled card. If you do, you may cast the copy without paying its mana cost.

Akroma's Memorial

Creatures you control have flying, first strike, vigilance, trample, haste, and protection from black and from red.

Assemble the Legion

At the beginning of your upkeep, put a muster counter on Assemble the Legion. Then create a 1/1 red and white Soldier creature token with haste for each muster counter on Assemble the Legion.

Sol Ring

Akroma's Blessing

Choose a color. Creatures you control gain protection from the chosen color until end of turn.
Cycling {W} ({W}, Discard this card: Draw a card.)

Deadeye Navigator

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Deadeye Navigator is paired with another creature, each of those creatures has "{1}{U}: Exile this creature, then return it to the battlefield under your control."