Uumuu

Behaviour and Tactics
Uumuu floats around the room, slowly homing into the player and occasionally using one of two attacks:


 * Burst: Uumuu will fill the arena with small bursts of lightning. Each lightning burst lasts for about one second. The lightning bursts appear in random spaces throughout the arena but thankfully they do leave some safe areas for The Knight to stand. The lightning bursts become dangerous at different times. The entire attack lasts for about two and a half seconds.
 * Chase: Uumuu will create a small burst of lightning where the Knight is, similarly to Volt Twisters. Uumuu will continue to create a new small burst of lightning every second for about six seconds. Each burst persists for about two seconds and each new burst will appear where the Knight is so constant movement is necessary.

Uumuu cannot be harmed normally, as its vulnerable core is protected by a membrane that deflects the player's attacks and shields it from Spells. However, after dodging attacks for a short time Quirrel will appear to help the Knight, leaping around the battlefield and occasionally popping Uumuu's shield. This will deflate Uumuu, leaving it open to attacks for a few seconds.

Although Uumuu may only have two attacks, they're both quite hard to dodge, and their pattern leaves few opportunities for healing. In addition, Uumuu's erratic movements and the very sparse opportunities for hitting it compared to its health pool result in a very drawn-out battle.

Get in as many hits as possible when Uumuu's shield is popped, and be prepared to dodge an attack right after. In desperate times, this can be an opportunity to heal instead. Avoid jumping in the water below a platform in the arena, as this greatly slows movement.

As with most boss fights, Quick Focus is highly recommended. SOUL-generating charms like Soul Catcher/Soul Eater, Kingsoul, and Grubsong are also very important in this fight, as chances to hit Uumuu and consequently to gather the SOUL needed for healing are quite rare. Great Slash and a Pure Nail are recommended in order to make short work of Uumuu.

Uumuu can be completely killed by using the Abyss Shriek three times with Shaman Stone allowing it to be beaten in one cycle given that enough SOUL has been gathered before the fight.

Godhome Uumuu
While in Godhome in the Pantheon or Hall of Gods Quirrel will no longer be at the player's side to break Uumuu's protective membrane. However Uumuu does gain a new attack in which it summons two Oomas that slowly float up until they disappear from the top of the screen. Getting these Ooma's explosive cores to collide with Uumuu will break it's shield.

There are a couple methods of making Uumuu vulnerable:
 * Have the Knight at an angle where the Ooma is right between it and Uumuu then strike the Ooma in Uumuu's direction.
 * If the Ooma is in close proximity to Uumuu or even behind/directly inside it then use a ranged spell such as Vengeful Spirit to trigger the Ooma.
 * The trickiest method is to dispatch the Ooma while you are between it and Uumuu then kite out the homing explosive core so that it is guided into Uumuu.

Trivia

 * The Uumuu fight is one of three fights in the game where an NPC aids the player, the other two are the Traitor Lord fight, where Cloth joins in, and the battle against The Hollow Knight, where Hornet helps defeat the boss.
 * Uumuu is among the few bosses who have to be beaten in order to get one of the endings.

Ууму