Ride of the Valkiries Achievement
Ride of the Valkiries50
Catch the fish while being attacked by jellyfish
Jellyfish are introduced during the Housekeeper levels. Large jellyfish are slow and eat your coins, while small jellyfish are fast but do not eat your coins. I earned this on the 10th level of Housekeeper. I am unsure if this can unlock anywhere else, but I got it by skewering the snail right before the jellyfish reached me.