Sea Monsters Mahjong is mahjong solitaire with an ocean cast — krakens, dolphins, mermaids — and the standard rule that a tile is only selectable when it's on top of a stack with a free side.
The sea creatures are distinct enough to scan quickly, which matters in a format where finding the pair is most of the work.
Only tiles on top of a stack with no blocks on their left or right side — the standard mahjong solitaire constraint.
It's built as a relaxed underwater take on the format, with hints and extra time available rather than pressure.
Yes — tap to match. Nothing to install.