Shock

Slickshot Show-Off

Flying, haste
Whenever you cast a noncreature spell, Slickshot Show-Off gets +2/+0 until end of turn.
Plot {1}{R} (You may pay {1}{R} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Mountain

Dreadmaw's Ire

Until end of turn, target attacking creature gets +2/+2 and gains trample and "Whenever this creature deals combat damage to a player, destroy target artifact that player controls."

Burn Together

Target creature you control deals damage equal to its power to any other target. Then sacrifice it.

Callous Sell-Sword

Callous Sell-Sword enters with a +1/+1 counter on it for each creature that died under your control this turn.

Callous Sell-Sword // Burn Together

Monastery Swiftspear

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Turn Inside Out

Target creature gets +3/+0 until end of turn. When it dies this turn, manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Blackcleave Cliffs

Blackcleave Cliffs enters tapped unless you control two or fewer other lands.
{T}: Add {B} or {R}.

Harried Spearguard

Haste
When Harried Spearguard dies, create a 1/1 black Rat creature token with "This creature can't block."

Might of the Meek

Target creature gains trample until end of turn. It also gets +1/+0 until end of turn if you control a Mouse.
Draw a card.

Jagged Barrens

Jagged Barrens enters tapped.
When Jagged Barrens enters, it deals 1 damage to target opponent.
{T}: Add {B} or {R}.

Monstrous Rage

Target creature gets +2/+0 until end of turn. Create a Monster Role token attached to it. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has trample.)

Cacophony Scamp

Whenever Cacophony Scamp deals combat damage to a player, you may sacrifice it. If you do, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
When Cacophony Scamp dies, it deals damage equal to its power to any target.

Heartfire Hero

Valiant — Whenever Heartfire Hero becomes the target of a spell or ability you control for the first time each turn, put a +1/+1 counter on it.
When Heartfire Hero dies, it deals damage equal to its power to each opponent.

Leyline of Resonance

If Leyline of Resonance is in your opening hand, you may begin the game with it on the battlefield.
Whenever you cast an instant or sorcery spell that targets only a single creature you control, copy that spell. You may choose new targets for the copy.

Clockwork Percussionist

Haste
When Clockwork Percussionist dies, exile the top card of your library. You may play it until the end of your next turn.

Felonious Rage

Target creature you control gets +2/+0 and gains haste until end of turn. When that creature dies this turn, create a 2/2 white and blue Detective creature token.