not rolled by the roulette
Tempest Shield is a spell that reserves mana to empower your shield, granting spell block chance and immunity to shock. While active, whenever you block, you deal damage to the enemy that hit you with an arc of lightning that chains to nearby enemies.
If you don't find it useful, think of it as free MTX for your shield!
Level requirement: 16.
The roulette doesn’t roll this gem, so its delivery options haven’t been worked out.