msem-instigator

Whenever one or more cards are put into an opponent's graveyard from their hand or library, you may exile the top card of each player's library. Until your next turn, you may cast a card from among those exiled cards and you may spend mana as though it were mana of any type to cast that spell.

Each Merfolk and Wizard you control has “Whenever this creature attacks, abound.” (To abound, you may cast a spell that costs less than that creature from your hand without paying its mana cost.)

{T}: Add one mana of any color.
{3}, {T}, Sacrifice Coveted Heirloom: Draw a card.
Tap three untapped artifacts you control: Return Coveted Heirloom from your graveyard to the battlefield.

Nightwatch Rallier enters the battlefield with X +1/+1 counters on it.
Other artifact creatures you control get +1/+1 for each +1/+1 counter on Nightwatch Rallier.

Whenever you cast an instant or sorcery spell, you may have Xenocrata's Fleet become a 4/4 Ship artifact creature with haste until end of turn.
Whenever Xenocrata's Fleet deals combat damage to an opponent, create that many 1/1 red Warrior creature tokens.