D20, and the Dice of Fortune

[TJ1524]

Good: Does 10-30 damage to your target.
Bad: Does 10-30 damage to yourself.

Edit:
Now that things are clearer: I will put more.
Good:
Spawns a prop around you
Next attack guarantees a proc off of the weapon you hold.
Gain 10 mobility for some seconds.
Gain 20 stability for some seconds.

Bad:
Put yourself into an ice cube.
Pushed into the air.
Head explodes.
Set on fire.