The Bow/Crossbow skill starts with a single arrow fired at the nearest enemy, followed by another and the next nearest and so on, up to a maximum of 10 targets. If 10 targets are not present it starts over at the first target. This leads to a visually pleasing sine wave, plus whatever "on-hit" modifiers resulting in arrows going through multiple targets, explosions, and/or meteors falling from the sky.
I have yet to see any skill in any game that's as satisfying as this. I get that it's underpowered, I get that many people don't like it. I just want to see something else like it before I'm too old and messed up to play games ever again.