Converge -- Search your library for a creature, instant, or sorcery card with mana value less than or equal to the number of colors of mana spent to cast this spell, exile that card, then shuffle. You may cast that card without paying its mana cost.
{3}{W}{W}
Cataclysmic Gearhulk
Artifact Creature - Construct
Vigilance
When Cataclysmic Gearhulk enters the battlefield, each player chooses an artifact, a creature, an enchantment, and a planeswalker from among the nonland permanents they control, then sacrifices the rest.
4 /
5
{3}
Chief of the Foundry
Artifact Creature - Construct
Other artifact creatures you control get +1/+1.
2 /
3
{4}{R}{R}
Combustible Gearhulk
Artifact Creature - Construct
First strike
When Combustible Gearhulk enters the battlefield, target opponent may have you draw three cards. If the player doesn't, you mill three cards, then Combustible Gearhulk deals damage to that player equal to the total mana value of those cards.
6 /
6
{3}
Foundry Inspector
Artifact Creature - Construct
Artifact spells you cast cost {1} less to cast.
3 /
2
{4}{B}{B}
Noxious Gearhulk
Artifact Creature - Construct
Menace
When Noxious Gearhulk enters the battlefield, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.
5 /
4
{2}{B}
Painful Truths
Sorcery
Converge -- You draw X cards and you lose X life, where X is the number of colors of mana spent to cast this spell.
{2}{R}
Radiant Flames
Sorcery
Converge -- Radiant Flames deals X damage to each creature, where X is the number of colors of mana spent to cast this spell.
{3}{U}
Roilmage's Trick
Instant
Converge -- Creatures your opponents control get -X/-0 until end of turn, where X is the number of colors of mana spent to cast this spell.
Draw a card.
{X}{G}{U}
Skyrider Elf
Creature - Elf Warrior Ally
Flying
Converge -- Skyrider Elf enters the battlefield with a +1/+1 counter on it for each color of mana spent to cast it.
0 /
0
{1}{W}{U}
Spell Queller
Creature - Spirit
Flash
Flying
When Spell Queller enters the battlefield, exile target spell with mana value 4 or less.
When Spell Queller leaves the battlefield, the exiled card's owner may cast that card without paying its mana cost.
2 /
3
{4}{U}{U}
Torrential Gearhulk
Artifact Creature - Construct
Flash
When Torrential Gearhulk enters the battlefield, you may cast target instant card from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.
5 /
6
{3}{G}{G}
Verdurous Gearhulk
Artifact Creature - Construct
Trample
When Verdurous Gearhulk enters the battlefield, distribute four +1/+1 counters among any number of target creatures you control.
4 /
4
{X}{X}
Walking Ballista
Artifact Creature - Construct
Walking Ballista enters the battlefield with X +1/+1 counters on it.
{4}: Put a +1/+1 counter on Walking Ballista.
Remove a +1/+1 counter from Walking Ballista: It deals 1 damage to any target.
0 /
0
{3}{G}
Woodland Wanderer
Creature - Elemental
Vigilance, trample
Converge -- Woodland Wanderer enters the battlefield with a +1/+1 counter on it for each color of mana spent to cast it.