Siege Modification

Enchant creature or Vehicle
As long as enchanted permanent is a Vehicle, it's a creature in addition to its other types.
Enchanted creature gets +3/+0 and has first strike.

Madcap Experiment

Reveal cards from the top of your library until you reveal an artifact card. Put that card onto the battlefield and the rest on the bottom of your library in a random order. Madcap Experiment deals damage to you equal to the number of cards revealed this way.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Reaver Titan

Void Shields — Protection from mana value 3 or less
Gatling Blaster — Whenever Reaver Titan attacks, it deals 5 damage to each opponent.
Crew 4 (Tap any number of creatures you control with total power 4 or more: This Vehicle becomes an artifact creature until end of turn.)

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Brute Force

Target creature gets +3/+3 until end of turn.

Simian Spirit Guide

Exile Simian Spirit Guide from your hand: Add {R}.

Elvish Spirit Guide

Exile Elvish Spirit Guide from your hand: Add {G}.

Samut, Tyrant Smasher

Creatures you control have haste.
−1: Target creature gets +2/+1 and gains haste until end of turn. Scry 1.

Start Your Engines

Vehicles you control become artifact creatures until end of turn. Creatures you control get +2/+0 until end of turn.