vortex grenades

[Myriad]

Leaving aside the advisability of using these in game, did anyone ever write any rules for these devices?

[Charax]

Grenade, explodes with the effect of Vortex of Chaos, every turn at the start of the turn it scatters D6 yards and you reroll the radius. Dissipates on a scatter of 6" or the turn after it reaches 4 yards radius (to stop it completely dominating the game...even though it probably should.)