Soulbright Seeker

As an additional cost to cast this spell, behold an Elemental or pay {2}. (To behold an Elemental, choose an Elemental you control or reveal an Elemental card from your hand.)
{R}: Target creature you control gains trample until end of turn. If this is the third time this ability has resolved this turn, add {R}{R}{R}{R}.

Lightning Skelemental

Trample, haste
Whenever this creature deals combat damage to a player, that player discards two cards.
At the beginning of the end step, sacrifice this creature.

Ball Lightning

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice this creature.

Ashen Reaper

Menace
At the beginning of your end step, put a +1/+1 counter on this creature if a permanent was put into a graveyard from the battlefield this turn.

Invasion of Azgol

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When this Siege enters, target player sacrifices a creature or planeswalker of their choice and loses 1 life.

Invasion of Azgol // Ashen Reaper

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Aether Vial

At the beginning of your upkeep, you may put a charge counter on this artifact.
{T}: You may put a creature card with mana value equal to the number of charge counters on this artifact from your hand onto the battlefield.

Champion of the Path

As an additional cost to cast this spell, behold an Elemental and exile it. (Exile an Elemental you control or an Elemental card from your hand.)
Whenever another Elemental you control enters, it deals damage equal to its power to each opponent.
When this creature leaves the battlefield, return the exiled card to its owner's hand.

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.