Aqua droids are specialized combat droids designed for underwater operations, and were part of the arsenal of the Confederacy of Independent Systems (CIS) during the Clone Wars and were used to bolster their ability to wage war in aquatic environments.
One of the notable deployments of aqua droids was during the Battle of Mon Cala, where they were used to support the local separatist forces against the Mon Calamari and their Republic allies. They played a significant role in the initial successes of the CIS forces by leveraging their underwater combat proficiency.
Aqua droids showcase the strategic diversity of the CIS droid army, able to adapt to various combat scenarios, including specialized environments like underwater, which typical infantry units could not handle.