Flight Spellbomb

{T}, Sacrifice this artifact: Target creature gains flying until end of turn.
When this artifact is put into a graveyard from the battlefield, you may pay {U}. If you do, draw a card.

Scrapwork Mutt

When this creature enters, you may discard a card. If you do, draw a card.
Unearth {1}{R} ({1}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Clan Crafter

Commander creatures you own have "{2}, Sacrifice an artifact: Put a +1/+1 counter on this creature and draw a card."

Gut, True Soul Zealot

Whenever you attack, you may sacrifice another creature or an artifact. If you do, create a 4/1 black Skeleton creature token with menace that's tapped and attacking. (It can't be blocked except by two or more creatures.)
Choose a Background (You can have a Background as a second commander.)

Mishra's Research Desk

{1}, {T}, Sacrifice this artifact: Exile the top two cards of your library. Choose one of them. Until the end of your next turn, you may play that card.
Unearth {1}{R} ({1}{R}: Return this card from your graveyard to the battlefield. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Experimental Synthesizer

When this artifact enters or leaves the battlefield, exile the top card of your library. Until end of turn, you may play that card.
{2}{R}, Sacrifice this artifact: Create a 2/2 white Samurai creature token with vigilance. Activate only as a sorcery.

Panic Spellbomb

{T}, Sacrifice this artifact: Target creature can't block this turn.
When this artifact is put into a graveyard from the battlefield, you may pay {R}. If you do, draw a card.

Ichor Wellspring

When this artifact enters or is put into a graveyard from the battlefield, draw a card.

Implement of Combustion

{R}, Sacrifice this artifact: It deals 1 damage to target player or planeswalker.
When this artifact is put into a graveyard from the battlefield, draw a card.

Dragonspark Reactor

Whenever this artifact or another artifact you control enters, put a charge counter on this artifact.
{4}, Sacrifice this artifact: It deals damage equal to the number of charge counters on it to target player and that much damage to up to one target creature.

Chromatic Star

{1}, {T}, Sacrifice this artifact: Add one mana of any color.
When this artifact is put into a graveyard from the battlefield, draw a card.