Warstorm Surge

Whenever a creature enters the battlefield under your control, it deals damage equal to its power to any target.

Impact Tremors

Whenever a creature enters the battlefield under your control, Impact Tremors deals 1 damage to each opponent.

Electropotence

Whenever a creature enters the battlefield under your control, you may pay {2}{R}. If you do, that creature deals damage equal to its power to any target.

Pandemonium

Whenever a creature enters the battlefield, that creature's controller may have it deal damage equal to its power to any target of their choice.

Terror of the Peaks

Flying
Spells your opponents cast that target Terror of the Peaks cost an additional 3 life to cast.
Whenever another creature enters the battlefield under your control, Terror of the Peaks deals damage equal to that creature's power to any target.

Witty Roastmaster

Alliance — Whenever another creature enters the battlefield under your control, Witty Roastmaster deals 1 damage to each opponent.

Halana, Kessig Ranger

Reach
Whenever another creature enters the battlefield under your control, you may pay {2}. When you do, that creature deals damage equal to its power to target creature.
Partner (You can have two commanders if both have partner.)

Alena, Kessig Trapper

First strike
{T}: Add an amount of {R} equal to the greatest power among creatures you control that entered the battlefield this turn.
Partner (You can have two commanders if both have partner.)