Mercurial Chemister

{U}, {T}: Draw two cards.
{R}, {T}, Discard a card: Mercurial Chemister deals damage to target creature equal to the discarded card's mana value.

Niv-Mizzet, the Firemind

Flying
Whenever you draw a card, Niv-Mizzet, the Firemind deals 1 damage to any target.
{T}: Draw a card.

Jaya Ballard, Task Mage

{R}, {T}, Discard a card: Destroy target blue permanent.
{1}{R}, {T}, Discard a card: Jaya Ballard, Task Mage deals 3 damage to any target. A creature dealt damage this way can't be regenerated this turn.
{5}{R}{R}, {T}, Discard a card: Jaya Ballard deals 6 damage to each creature and each player.

Nightscape Master

{U}{U}, {T}: Return target creature to its owner's hand.
{R}{R}, {T}: Nightscape Master deals 2 damage to target creature.

Jeska, Warrior Adept

First strike, haste
{T}: Jeska, Warrior Adept deals 1 damage to any target.

Shadow Guildmage

{U}, {T}: Put target creature you control on top of its owner's library.
{R}, {T}: Shadow Guildmage deals 1 damage to any target and 1 damage to you.

Banshee

{X}, {T}: Banshee deals half X damage, rounded down, to any target, and half X damage, rounded up, to you.

Cruel Sadist

{B}, {T}, Pay 1 life: Put a +1/+1 counter on Cruel Sadist.
{2}{B}, {T}, Remove X +1/+1 counters from Cruel Sadist: It deals X damage to target creature.

Brimstone Mage

Level up {3}{R} ({3}{R}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 1-2
2/3
{T}: Brimstone Mage deals 1 damage to any target.
LEVEL 3+
2/4
{T}: Brimstone Mage deals 3 damage to any target.

Brion Stoutarm

Lifelink
{R}, {T}, Sacrifice another creature: Brion Stoutarm deals damage equal to the sacrificed creature's power to target player or planeswalker.

Vein Drinker

Flying
{R}, {T}: Vein Drinker deals damage equal to its power to target creature. That creature deals damage equal to its power to Vein Drinker.
Whenever a creature dealt damage by Vein Drinker this turn dies, put a +1/+1 counter on Vein Drinker.

Prodigal Sorcerer

{T}: Prodigal Sorcerer deals 1 damage to any target.

Kiku, Night's Flower

{2}{B}{B}, {T}: Target creature deals damage to itself equal to its power.

Apprentice Sorcerer

{T}: Apprentice Sorcerer deals 1 damage to any target. Activate only during your turn, before attackers are declared.

Titan of Eternal Fire

Each Human creature you control has "{R}, {T}: This creature deals 1 damage to any target."

Minion of Tevesh Szat

At the beginning of your upkeep, Minion of Tevesh Szat deals 2 damage to you unless you pay {B}{B}.
{T}: Target creature gets +3/-2 until end of turn.

Ghost-Lit Raider

{2}{R}, {T}: Ghost-Lit Raider deals 2 damage to target creature.
Channel — {3}{R}, Discard Ghost-Lit Raider: It deals 4 damage to target creature.

Endbringer

Untap Endbringer during each other player's untap step.
{T}: Endbringer deals 1 damage to any target.
{C}, {T}: Target creature can't attack or block this turn.
{C}{C}, {T}: Draw a card.

Cuombajj Witches

{T}: Cuombajj Witches deals 1 damage to any target and 1 damage to any target of an opponent's choice.

Abyssal Hunter

{B}, {T}: Tap target creature. Abyssal Hunter deals damage equal to Abyssal Hunter's power to that creature.

Mawcor

Flying
{T}: Mawcor deals 1 damage to any target.

Capricious Sorcerer

{T}: Capricious Sorcerer deals 1 damage to any target. Activate only during your turn, before attackers are declared.

Prodigal Pyromancer

{T}: Prodigal Pyromancer deals 1 damage to any target.

Crimson Hellkite

Flying
{X}, {T}: Crimson Hellkite deals X damage to target creature. Spend only red mana on X.