Alternatively, use "Rescue Rabbit" to Special Summon two copies of "Aqua Madoor", then use this card to make them level 6 to Xyz Summon "Magi Magi ☆ Magician Gal".
This card is more suited for "Deep Sea Diva" than "A Legendary Ocean". You can Summon a Level 2 monster, boost both monsters by 2 Levels, and Synchro for 8.
Special Summon "Ronintoadin" and another Level 2WATER monster. Use this card's effect, then Normal Summon a Level 4 monster and overlay for a 3-part Rank 4Xyz Monster.
Use with any non-Tuner WATER monster and "Fishborg Launcher" to make a WATER Synchro Monster whose Level is 1 or 3 greater than the non-Tuner's Level.
This card makes a valuable addition to a Fish Deck. After the effect of "Superancient Deepsea King Coelacanth" is used, a total of 5 WATER monsters are in play; thus you can raise all of their Levels by 5, allowing you to Summon virtually any Xyz Monster.
If you Summon Level 4 monsters with "Coelacanth", you can increase their Levels with this card's effect to Xyz Summon two copies of "Number 9: Dyson Sphere".