A wiff & a half (event idea)
Here's one for you Dm's that want a not actual surprise attack, attack. The players are walking around when an arrow comes from the sky & hits one of the players. This should set the party into a frenzy to find who did this, & while this happens another arrow comes & almost hits another team member. At this point make them roll initiatives & have them freak out at what is happening. After awhile of trying to figure out who is doing this, they will find a lone bowman trying to hit a bird & missing. This bowman is in the direction that the other two arrows came from are. At this point the players do whatever they decide to do next.