This card's name is treated as "Umi". All WATER monsters gain 200 ATK and DEF. Once per turn, during your Main Phase: You can have all WATER monsters you currently control gain Levels equal to the number of WATER monsters you currently control, until the End Phase.
Allows all WATER monsters to gain additional levels equal to the number of WATER monsters on your Field.
Takes up 1 of your backrow slot, potentially clogging your backrow.
Overall this card pales in comparison to A Legendary Ocean as “Umi” because it allows you to Normal Summon monsters with original level 5 to the field in order to use Sea Stealth Attack. The monsters level which you increase using Lemuria’s effect does not allow you to use Sea Stealth Attack if your monster’s original level is not level 5 or above.