Mermail

"Mermail" is an archetype of WATER-Attribute and Aqua or Sea Serpent-Type monsters, introduced in the Abyss Rising. They are based on Mermaids, outifitted with armor, hence "mail". They are related to the "Abyss" archetype, but they look like "Gishki" monsters.

Playing Style
When lower-Level "Mermail" monsters are sent to the Graveyard, their effects activate, letting them swarm the field. The higher-Level "Mermail" monsters can Special Summon themselves with relative-ease by sending other "Mermail" to the Graveyard, which will also trigger their effects.