I was convinced my 16-year old wealthy fort was totally goblin- and kobold- free. Now I'm spotting thieves at every door and ambushes at every gate. I don't know what happened, but I think since I updated straight from 31.14, maybe there was an old bug stopping invasions or suchlike. It's lucky that my wall and moat were mostly finished by the time this started.
The most epic thing that happened, besides the caravan running right into a marksgoblin ambush, was when my legendary engraver spotted an ambush while heading to reload a cage trap (he shouldn't have been outside in the first place). As he fled I frantically summoned all my troops but they were mostly far away.
The engraver fled in panic along the edge of the moat. As he passed the gate, a lone figure sprang out. It was my lasher, now a skilled axedwarf, who had now gone and found himself a goblinite whip. Only he stood between a dozen speargoblins and one of the most valuable dwarves in the fort...
The first collapsed in pain after several strokes, finished by crushing his skull. Then the lasher went after the others, bringing another down before the remainder simply fled in panic before the dwarven tornado of lashing fury.
I was a bit disappointed actually, I was hoping he would have to make a Boromir-like last stand against overwhelming odds, but I'm not going to look a gift horse in the mouth either

From now on no one leaves the safety of the walls without military escort!