Static Orbs Charged Ground with the “Electrocuting Cascade” node is supposed to get additional damage over time per additional critical strike multiplier. This does indeed work for generic additional multiplier on items and even for specific spell critical multiplier (e.g. sorcerer passive tree), but does NOT work for the node “Critical Trajectory” in Static Orbs own skill tree, even though that just says “Critical Multiplier +X”.
Please correct me if this is for some semantic reason correct, but as far as I understand it, that node should affect the damage of Charged Ground.