Specifically Spark Generator from the Mage skill: Apprentice Sparking is supposed to add 2 damage to electric attacks, when an electric attack is played, spark generator flashes to show the buff, but the damage bonus is not applied.
Zap spells are type Arcane, not Electric, so the Spark Generator is making them Hard to Block, not adding damage. This confuses pretty much everyone, and has produced many, many threads. Here's mine: https://forums.cardhunter.com/threads/suggestion-sparks-and-zaps.2309/ (They've made changes to art and item names since I made that thread.)
For what it's worth, as a new player, +1 to Kalin and Howl's suggestion. I also thought it was a bug. I also wondered why I wasn't getting a -3 to block on my spark attacks. I see now reading the threads, but it is confusing.
