The Egg Cauldron first encountered Sonic, Tails and Chip during the trio's trip to Spagonia in the Tornado-1. Despite Orbot's warnings, Dr. Eggman had the incomplete Egg Cauldron fight the bi-plane, only to be forced into retreat. After being perfected, the Egg Caldron was sent to intercept Sonic, Tails and Chip when they were heading for Eggmanland, only for the vessel to face defeat again.
Powers and features
Thanks to the large fans that operate it, the Egg Cauldron is capable of intercontinental travel, and can keep up with the Tornado-1. The Egg Cauldron also has a large arsenal that acts as a base for Eggman's aerial troops. Its armaments, as seen in battle, consist of several missile launchers located around the top of the fortress itself, as well as a special cannon hidden inside the central hatch, that seemingly launches fireballs(though it is only used in the second fight, should the player take too long to fight the boss itself).
There is one primary way to beat this boss and one secondary method that only works during Act I:
Method One: Wait until Eggman launches a full-scale attack (When the player hears him saying "Go, fire all weapons."). After defeating all of the enemies, the large access door will remain open a couple of seconds. While it's open, shoot it by pressing whatever button is indicated five times. Repeat until destroyed.
Method Two: During Act I, it is possible to win the battle by simply surviving the onslaught of missiles and fighters attacking Sonic and Tails. After the two minutes and thirty seconds timer is up, the same cutscene plays as if the player defeated the Egg Cauldron with the first method. However, this approach will not work during Act II. Allowing the three minutes and thirty seconds timer to reach zero here will result in the Egg Cauldron launching what appears to be a massive fireball-like projectile from the central hatch, which automatically destroys the Tornado, costing the player a life.
If Sonic and Tails are defeated by the Egg Cauldron, the player will have to restart the whole act from the beginning.
Due to the mini-game Tornado Defense not being in the Wii/PlayStation 2 version, this fight is skipped entirely, meaning this is the only boss that does not appear on the Wii/PlayStation 2 version of Sonic Unleashed.
For some reason, Eggman is not surprised to see Sonic alive from the fall, even though Sonic has not visited him at Mazuri at this point (although this may be due to the Wii/PlayStation 2 versions of this game skipping the first Tornado Defense act, as Eggman does not meet Sonic since the opening cutscene until he arrives in Mazuri.).
This is the only boss that the player has to fight twice in the Xbox 360/PlayStation 3 version.