As you know, in chess composition the composers invent various pieces, which move or capture in various ways.
The IGM Petko Petkov from Bulgaria has written three articles for a group of pieces which have Marine names, and they are published in the site Julia's Fairies by Julia Vysotska from Latvia.
1) Part I – Siren, Triton, Nereid
2) Part II – Poseidon, Marine Knight, Marine Pawn
3) Part III – Scylla, Charybdis