The Boss Kettle for this boss can be found in the middle of Tentakeel Outpost, on a pyramid like hill.
Boss Appearance
The Octo Oven is a large industrial-grade oven propped up on some little castor wheels, much like a Flooder. It has eight sentient loaves of bread with Octarian faces on them inside of it, and each one even has a voice. On the Octo Oven, there is a small red eye-like sensor, which will move to follow the player. During the second phase, some of the ceramic walls of the oven will break, revealing some more machinery, such as a door with a warning symbol on it (Glazing Machine) and a larger optical sensor. The vents on top of it will also grow in size, extending upwards. During the third phase, the door with the warning symbol on it will open, and a large rod of ink sprayers will emerge. The loaves of bread will also gain some armored spots on them, each adorned with an Octarian bread company logo.
Walkthrough
Phase 1
The Octo Oven will try to line up one of its loaves at the player. The boss will then extend it, and quickly retract it.
The Octo Oven does this multiple times, until it does a short hop and extends out all its loaves. The Oven won't immediately pull the bread back, giving the player time to ink them and jump from loaf to loaf to get to the tentacle at the top of the oven. The player needs to fire at the tentacle to deal damage. After enough damage is done, the player super jumps to the ground and the next phase begins.
Phase 2
The Octo Oven doesn't change anything about its attack pattern, but gushers firing OctarianInk will appear, as well as a decrease in climbable walls. The gushers will stop if bread hits them, and they will be added back.
Phase 3
The Octo Oven will now extend a "glazing machine". The glazing machine will rotate around most of the arena and will give chase to the player while spewing out ink. The gushers are now strategically placed in areas that will get in the way of the player trying to outrun the machine. After this attack is over, an extremely large portion of the arena will be covered in Octarian Ink. In addition, the pre-existing loaves of bread now have armored spots that are uninkable and unclimbable and the loaves comes out quicker.