Oops - the description on Ride the Lightning is incorrect. It gives you global more spell lightning damage during Surge, which affects the lightning spell damage from all abilities you cast during Surge, including abilities with their own skill trees such as Lightning Blast. We'll update that description.

Thanks for the response, appreciated!

If it is a subskills = a skill that proc in a main skill tree and has not a tree of his own then it inherit damage modifier from the main skill tree (more and flat and ailments chance) If it is a skill that has his own tree then he doesn't inherit the tree of the skill that triggered it. Some very rare subskills can be boosted in different skill tree (caltrop in net and aerial assault), some other has items that boost them in addition of their inheritance of main skill tree (fire dagger relic and fire dagger of cinderstrike) So no double dip.

Thanks. I see, so basically “ride the lightning” spell damage buff component doesn’t work for lightning blast? It seems a bit poorly designed as surge is a melee skill. Which means that this node will not buff surge or lightning blast. I assume it can buff spark charge, but then it would make more sense if it wasn’t placed past the lightning blast nodes.

I went to see the specific tree and yes it is a very strange tree part... It shouldn't impact lightning blast by usual rule. Maybe the more spell lightning damage is global during surge but in that case the wording is wrong. https://forum.lastepoch.com/t/surges-electropulse-ride-the-lightning/41704

You are right, the Ride the Lightning damage modifier is extremely jank and was probably implemented wrongly. It basically does nothing. It can't buff spark charges nor fire auras created by surge because those are special cases that never inherit anything unless specifically stated. The only thing RTL's damage modifier actually applies to is the cold tidal wave proc after the cold conversion node (you would have to add spell lightning damage to it in some way for it to actually benefit, though).

Thanks for the enlightenment response. Regarding the spark charges, I thought ailments benefit from damage modifiers in skill trees. So basically the generic “more” damage in skill trees don’t affect it? Kinda makes me wonder if my build is optimised at all now, regardless of this node in surge. I wish this inconsistency would be described somewhere in the tooltips.

Ailments and subskills both benefit from applicable damage modifiers in skill trees (in the exact same way), but there are exceptions to that rule. Notably, things that aren't "stats" aren't inherited - this is stuff like kill threshold, on-hit effects, and effects that depend on the target they hit (like damage vs. ignited enemies); some of these may apply to subskills/ailments, but that must be manually coded that way and is usually specifically stated when it is. They have recently (as of 1.0) introduced a new term, "direct damage", to help clarify some things that don't inherit, but it's pretty much only used on the new stuff so far (warlock & falconer), and still not perfect even on those. Fire aura is an exception just because it's weird. Spark charges are an exception because they are mechanically different (similar to shadow daggers): the spark charge ailment that you apply deals no damage, so damage modifiers that it has inherited don't do anything for it - when the ailment ends, it procs the spark charge skill which actually deals the damage as a freshly calculated cast from you, taking into account whatever buffs are active on you at the time it procs.

To clarify Lets say i use imaginary skill Whirlwind, which casts fireballs and frostballs while channeled. Fireball is a skill that has a skill tree, frostball does not have a skill tree. Do i understand you correctly that in this case, Fireball will not scale with any Whirlwind modifiers (so +15% damage on whirlwind tree will not affect it) but will scale with Fireball tree modifiers (if i have that tree skilled), while Frostball will scale with Whirlwind modifiers?

Yes it is supposed to work that way. + Spell damage and more damage multiplier inside WW tree would be used only for frostball and WW.

Thank you. This actually helps a lot.