MOBS / BOSS / MINI BOSSES lightning - sparks dmg output

Please review the dmg outpout of lightning sparks from mobs boss etc, its seems that effectively wipes me out instantly even though I have armor-energy shield - elemental capped + increased max resist of the element type, no matter because sparks wipes ES and half of hp with 1 spark, bosses wipes you with 1 spark.
Should be and error number behind this dmg output, I lost few maps because encountering this type of damage on enemies.