|HP:||2000, 2600 (Ω)|
|Attacks:||Sonic Boom, Saint Light, Holy Shock|
|Main site:||Secret Area 3|
|MegaMan Battle Network 3|
Template:Nihongo, also known as "S" and "UnderKing" (however, in Japanese version, Serenade is female), is a NetNavi from MegaMan Battle Network 3, and is the ruler of the Undernet. When Lan is asked to obtain the Forbidden Program called "GigaFreeze", which is able to freeze Alpha in case it awakens, he goes to Undernet and has to defeat several ranked Navis to reach "S", the rank 1 Navi that protects the program. After defeating rank 2, MistMan (White version) or BowlMan (Blue version), he discovers the Navi is called Serenade and is located in the server of the Undernet. MegaMan finds the server in the Ura Inn, where Serenade's voice can be heard and says that if he want the Forbidden Program, he must be a "Chosen One" to hold it, or the program would freeze him forever. MegaMan is able to take it and leaves, and Serenade is surprised to see that other Navi is able to hold it. Later, MegaMan tries to use the program against Bass when he was taking Alpha after DrillMan's defeat, but it sees he is the other "Chosen One" mentioned by Serenade and is able to stop the program.
It's believed Mamoru is Serenade's operator, as he has Serenade's emblem on his wheelchair, and his father created the Undernet.
After completing the game and completing other quests (like defeating Beta Navis and collecting all normal BattleChips), the player can enter in a Secret Area from the Undernet server, where he fights against DarkMan and JapanMan before meeting Serenade. Serenade recognizes MegaMan's power for being able to defeat JapanMan and DarkMan, and says the source of his power is mercy, and he wins because he loves and respect his enemies. After defeat, Serenade reveals he fought against Bass in the past, winning after a battle that last days. MegaMan receives Rank 1 and a side-quest will be available after logging out and them returning to the Secret Area, a time attack against several Alpha NetNavis with a Extra Folder. The player can obtain the BattleChip Serenade S (White version) or DarkAura A (Blue version) if a new record is set in all Navis.
- Sonic Boom: If Serenade is able to move up or down, any attacks that hit him will be reflected down the row in a sonic boom.
- Saint Light: Serenade fires an orb that slowly zigzags across the battlefield.
- Holy Shock: Seranade stands at the front of his area and puts his palm forward. Panels will flash and damage the player if he's standing on them, and also a gust of wind will push the player backwards.