unstable, 5 minutes/catalyst

As two actions, you can create this bomb. As an action, a creature can throw this bomb at a point within 5 meters, where it explodes on impact. Thunderous clouds spreads to fill a sphere for the duration. The sphere spreads around corners, and its area is heavily obscured. It lasts for the duration or until a wind of moderate or greater speed (at least 15 kilometers per hour) disperses it. A creature that enters the spell’s area for the first time on a turn or starts its turn there must make a Fortitude saving throw.

On a failure, it takes 2d10 lightning damage and is deafened until the end of its next turn.

On a critical failure, it takes twice as much damage.

On a success, it takes half as much damage.

On a critical success, it takes no damage.

Augment
You can augment this concoction with the following options, expending catalysts for each option.
  • You can increase the damage by 1d10 for every two additional catalyst expended.

  • You can expend 1 additional catalyst so duration changes to 1 hour/catalyst.