Fish Simulator
Every fish carries a genome that sets its traits, its colour and its pattern. They eat, age, compete, breed with crossover and mutation, and bigger fish hunt smaller ones. In the sandbox you set the food and the pond, spawn a species by hand, inspect any fish’s genome, cull it or force a pairing, and pause, step or fast-forward time while the population graph and lineages unfold. In duel mode you spend a fixed trait budget on a species and win by holding a majority of the pond.