Valkyrie's Call + Simulacrum Synthesizer + Umbral Collar Zealot

Valkyrie's Call

Simulacrum Synthesizer

Umbral Collar Zealot

How it works

1. Cast the Vehicle by paying its mana cost.
2. When the Vehicle enters the battlefield, Simulacrum Synthesizer triggers, creating a 0/0 Construct artifact creature token that gets +1/+1 for each artifact you control.
3. Activate the Vehicle's crew ability by tapping the Construct, causing the Vehicle to become an artifact creature until end of turn.
4. Activate Umbral Collar Zealot by sacrificing the Vehicle.
5. When the Vehicle dies, Valkyrie's Call triggers, returning the Vehicle from your graveyard to the battlefield. It will not be an Angel because the Vehicle is no longer a creature and cannot gain creature types.
6. When the Vehicle enters the battlefield, Simulacrum Synthesizer triggers, creating a 0/0 Construct artifact creature token that gets +1/+1 for each artifact you control.
7. Resolve the Umbral Collar Zealot ability.
8. Repeat from step 3.

This ingenious loop turns a regular Vehicle into an endless engine of creation and sacrifice, fueled by the passive, watchful presence of Simulacrum Synthesizer. By using Umbral Collar Zealot to sacrifice the Vehicle, you trigger Valkyrie's Call to continuously resurrect it, which in turn feeds the Simulacrum Synthesizer to churn out an endless army of scaling Construct tokens.