BOOBYTRAP

Transmutation cantrip

Casting Time: 2 actions
Components: S
Duration: 1 minute
Range: Touch
Target: 

You infuse one Tiny object with volatile arcane energy, rigging it to detonate as soon as it is touched. You can only infuse one object at a time. If any creature other than you touches that object before the end of the spell's duration, they must succeed on a Dexterity saving throw or take 2d4 force damage. If you infuse an object past the maximum number with this spell before the previous infusion ended, the previous object loses its infusion.

You can infuse an additional object as a 5th (two objects), 11th (three objects), and 17th-level (four objects) spellcaster.