Blitz Automaton

Prototype {2}{R} — 3/2 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Haste

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Blaster, Morale Booster

Modular 3
{X}, {T}: Move X +1/+1 counters from Blaster onto another target artifact. That artifact gains haste until end of turn. If Blaster has no +1/+1 counters on it, convert it. Activate only as a sorcery.

Blaster, Combat DJ

More Than Meets the Eye {1}{R}{G} (You may cast this card converted for {1}{R}{G}.)
Other nontoken artifact creatures and Vehicles you control have modular 1. (They enter with an additional +1/+1 counter on them. When they die, you may put their +1/+1 counters on target artifact creature.)
Whenever you put one or more +1/+1 counters on Blaster, convert it.

Blaster, Combat DJ // Blaster, Morale Booster

Towashi Guide-Bot

When Towashi Guide-Bot enters, put a +1/+1 counter on target creature you control.
{4}, {T}: Draw a card. This ability costs {1} less to activate for each modified creature you control. (Equipment, Auras you control, and counters are modifications.)

Forest

Power Depot

Power Depot enters tapped.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast artifact spells or activate abilities of artifacts.
Modular 1

Akki Battle Squad

Whenever one or more modified creatures you control attack, untap all modified creatures you control. After this phase, there is an additional combat phase. This ability triggers only once each turn. (Equipment, Auras you control, and counters are modifications.)

Dwarven Mine

({T}: Add {R}.)
Dwarven Mine enters tapped unless you control three or more other Mountains.
When Dwarven Mine enters untapped, create a 1/1 red Dwarf creature token.

Invigorating Hot Spring

Invigorating Hot Spring enters with four +1/+1 counters on it.
Modified creatures you control have haste. (Equipment, Auras you control, and counters are modifications.)
Remove a +1/+1 counter from Invigorating Hot Spring: Put a +1/+1 counter on target creature you control. Activate only as a sorcery and only once each turn.

Shambling Suit

Shambling Suit's power is equal to the number of artifacts and/or enchantments you control.

Tamiyo's Safekeeping

Target permanent you control gains hexproof and indestructible until end of turn. You gain 2 life. (A permanent with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Haywire Mite

When Haywire Mite dies, you gain 2 life.
{G}, Sacrifice Haywire Mite: Exile target noncreature artifact or noncreature enchantment.

Unwinding Clock

Untap all artifacts you control during each other player's untap step.

Grumgully, the Generous

Each other non-Human creature you control enters with an additional +1/+1 counter on it.

Arcbound Slasher

Modular 4 (This creature enters with four +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)
Riot (This creature enters with your choice of an additional +1/+1 counter or haste.)

Goblin Anarchomancer

Each spell you cast that's red or green costs {1} less to cast.

Rhythm of the Wild

Creature spells you control can't be countered.
Nontoken creatures you control have riot. (They enter with your choice of a +1/+1 counter or haste.)

Mountain

Slagstone Refinery

Whenever Slagstone Refinery or another nontoken artifact you control is put into a graveyard from the battlefield or is put into exile from the battlefield, create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")