Resourceful Return + Junk Diver

Junkheap Magpie —
Artifact Creature — Bird (U)
Flying
Sacrifice Junkheap Magpie: Return target creature card from your graveyard to your hand. If it’s an artifact creature card, draw a card.
1/1

Junk Diver + Tonic Peddler

Junk Peddler
Creature - Human Spellshaper (C)
, , Discard a card: Gain 1 life for each artifact card in your graveyard.
"Special price on that one."
2/2

tonic peddler/apex of power
uuuhhhh

Melekon, Manifestation of the Apex
Creature - Dragon Spellshaper
Flying
, discard your hand: Exile the top X cards of your library, where X is the number of cards discarded this way. You may cast those cards this turn. Add X mana of any colour.
5/5

Apex of Power × Mythos of Brokkos

Apex of Power + Outmuscle

Ambusher's Charge —
Instant (U)
Exile the top three cards of your library. Choose a creature card amongst them. You may have it deal damage equal to its power to target creature and you may cast it until the beginning of your next end step.


Edit: Mythos of Brokkos + Sunforger

Brokkos' Pendant —
Artifact — Equipment (R)
Equipped creature gets +3/+3.
, unattach Brokkos' Pendant: Return a permanent card from your graveyard to your hand.
Equip

Sunforger + March of the Returned

March of the Returned × Rabid Bloodsucker

Rabid Bloodsucker + Garruk's Warsteed

Sengir Sparkersucker
Creature - Vampire (R)
Flying
When Sengir Sparksucker enters the battlefield, remove a loyalty counter from any number of target planeswalkers. Then search your library for a planeswalker with loyalty X or less, where X is the number of loyalty counters removed this way. Put that card into your hand, then shuffle your library.
3/3

Garruk's Warsteed + Oathsworn Giant

Elspeth's Retinue

Creature - Human Knight
Vigilance
When Elspeth's Retinue enters the battlefield, you may search your library and/or graveyard for an Elspeth planeswalker. Reveal it, shuffle your library if you searched it, and put that card on top.
Whenever a source would deal damage to an Elspeth planeswalker you control, prevent 2 of that damage.
3/4

Oathsworn Giant + Leyline of the Void

Leyline of the Void + Fleshformer

Leyline Former
Creature - Human Wizard
If Leyline Former is in your opening hand, you may begin the game with it on the battlefield as an enchantment. (It loses all its other types.)
: You may put an enchantment card from your hand onto the battlefield.
"Dreams are only realities yet realized."
2/2

Fleshformer + Corpse Traders

Corpse Traders + Quasiduplicate

Identity Thief

Creature -- Shapeshifter (R)
When Identity Thief enters the battlefield, target opponent reveals their hand. You choose a creature card from it. That player discards that card. Identity Thief becomes a copy of that card.
"I'll be a better you than you ever could."
2/2

Quasiduplicate × Watchers of the Dead

Watchers of the Dead + Goblin Sappers

Goblin Contractor

Creature - Goblin Advisor
, : Another target creature you control of an opponent's choice gains menace and haste until end of turn.
, : Another target creature you control gains menace and haste until end of turn.
"Shouldn't have gone with the low bid..." - Mishra
2/1

goblin sappers/faerie conclave

Wormhole
Land
: Add .
: Add or . ~ deals 1 damage to you.
, : Target creature you control can't be blocked this turn. Sacrifice that creature at the end of combat.

Faerie Conclave + Unlikely Alliance

Unlikely Alliance × Swamp (this one, specifically)

swamp/ghostly prison

Noxious Miasma
Enchantment
Whenever a creature attacks you, it gets -2/-2 until end of turn, and you lose 1 life.

Ghostly Prison + Knight of the Pilgrim's Road