The Egg Dragoon is fought in a long, circular tunnel. During the battle, Dr. Eggman will switch between the Egg Dragoon's body and tail, the Egg Dragoon's attacks are dependent on what part Eggman is piloting. Whilst in the Egg Dragoon's body, Eggman attacks by either firing a large drill that can be avoided by using Quick Step, or by firing six rotating lasers that must be jumped over. Whilst in the Egg Dragoon's tail, Eggman attacks by shooting ice blasts at Sonic, which must be avoided by simply moving out of the way. Each part of the Egg Dragoon must be hit four times to defeat it. During the battle, the camera then changes to a 2-D perspective and the Egg Dragoon will shoot ice at Sonic that can be avoided by jumping over it. During these sections, Eggman tries to trap Sonic between two walls whilst shooting ice blasts at Sonic, Sonic must Wall Jump between these two walls while avoiding the ice blasts to attack the Egg Dragoon's head. If Sonic fails to do so after a short time, Eggman will smash the two walls together, crushing Sonic between them.
Once the Egg Dragoon's head has been hit four times, the battle changes. Dr. Eggman will not try to trap Sonic between two walls. Instead, Eggman performs a "Parallel Attack" where the Egg Dragoon's body and tail detach and attack simultaneously, and when the belly has been hit once, a portal opens up along the tunnel that sends Sonic and the Egg Dragoon into a long vertical tunnel. Sonic must dive towards the Egg Dragoon whilst avoiding its drill attack to hit the Egg Dragoon's belly. At the bottom of the tunnel, there is another portal which takes the player back to the normal area; to re-enter the vertical tunnel section, Sonic must attack the Egg Dragoon's belly again.
Once both parts of the Egg Dragoon's body are defeated, another mini-cutscene shows it crashing at the bottom of the vertical tunnel whilst Sonic simply lands there, unscathed. It takes a total of 8 hits to defeat the Egg Dragoon on Normal mode, and 10 hits to defeat it on Hard mode.
The Egg Dragoon is the only major boss that was not a final boss in the game it originated from.
However, it is the last Night boss to be battled in Sonic Unleashed and was the penultimate boss overall (after Dark Gaia).
The Egg Dragoon is the only console/PC boss to not appear on an advertisement in the game (the Death Egg robot and Perfect Chaos appeared in the Chao in Space posters in Speed Highway and City Escape and the Time Eater's name makes a cameo in Radical Highway on the 3DS version).
In the 2D sections of this boss, you can see the floating world piece that Eggmanland is built through the glass, the actual boss stage itself is the falling section of the original boss battle. However, unlike Unleashed, it never enters the Earth's core, as the Dragoon vanishes through a portal before hitting the floor plate and just lands on the plate when defeated.
The music for this level's Boss Gate found in White Space, rather than a remix of the music heard in the level, is a remix of E.G.G.M.A.N. from Sonic Adventure 2. The actual remix heard in the fight simply has part of it's backing track removed.
Even if Sonic does not deliver the final hit at the diving part, the cutscene still shows the Egg Dragoon falling from the vertical tunnel. Should the final hit be dealt in the running stage, the Dragoon is seen to start exploding and spinning into a portal, before the cutscene plays out as normal.
Egg Dragoon (in Hard Mode) takes the most number of hits to defeat out of any boss (including Rivals) in both versions of Sonic Generations.
In the boss trailer, Eggman can be seen riding (or rather standing) on top of the Egg Dragoon. This was most likely a glitch.