Tiamats are gigantic five-headed aquatic creatures with black scales and yellow eyes. They are at their strongest when they are battling at sea since they can move around very quickly and easily recover their HP every turn. They are unable to move around as freely on land. They are mostly used to guard castles because of this. Once Hydras become Tiamats, their breath loses its frost and it is replaced by evil energy. Unlike Hydras, they can now also let out a high pitch roar that can damage all units around them. Their attacks do extra damage to beings with the Red Element and the White Element. In Grand Edition, they lose their ability to recover their HP every turn on water.