Physical projectile attack damage + Lightning strike = 'd'

When I combine both, it appears a 'd' at the top right of Lightning strike, but I don't know what exactly changes. The description seems unaltered except for the mana cost which rises.

Is this working?

I haven't tried it out myself, but based on gem description it should not increase damage. Lightning strike has a melee physical damage and 50% of it is converted to lightning PROJECTILE damage. Physical projectile attack damage gem increases neither the melee physical nor the lightning projectile.

The part of the skill which is physical is a not projectile and the part where it is a projectile, it deals no physical damage.

yeopokemon is incorrect. Converted damage from physical still gets boosted by physical dmg mods.

The OP's combo will mean the projectiles do more dmg.

Right, LS tooltip lists damage only for direct hit, however, projectiles will benefit. You can try linking LMP too, it won't change your dps but I can assure you it ain't giving you two additional projectiles for free :)

i tried it, my usual combo is LS+Fire+Weaponele+Multi in BOR...

so put the stuff in some test gloves from my bor...
well tooltip says 22k with usual combo
and with phys projectile (instead of fire or weaponele) it was 8,5k....

the phys projectile was level 16 so not really shit for comparison.

well and it felt like 8k ;)... so ill dont waste ex for a high Quali one... seems shit for me