You play as… I guess a diver guy, throwing harpoons at walls and collecting incidental goldfish. At the end of every level is a golden harpoon; snag it to move on. The main mechanic involves the harpoon; lodged in a wall, you can use it to clamber up and over surfaces. If you run and jump on the harpoon in mid-air, you can ride it like a broom. The levels will introduce gizmos and complications, but these are the basics.
The game seems, at times, impossible — and it does the bare minimum to help the player along. Yet this is probably a good choice, as the solutions always are logical and in retrospect often obvious. Any level might contain two or three moments of head-slapping epiphany. A good test of a puzzle is when the solution always feels like it’s in the player’s hands, rather than being held at arm’s length — and that is the case here.
You can play Fishbane online here.