|This sanctuary now rings with the sound of combat - the end of the ancient duality of the Covenant is truly at hand.|
Gemini is considered as being the Prophet's retreat. It is somewhat of an unusual level, as it consists of a closed-quarter outside area and an open inside area. Teleporters can warp players up to two small balconies on the top of the inner area. Another teleporter warps players to the outside and back. There is a wide array of weapons from close ranged Brute Shots and the Energy Sword, to Carbines and a Beam Rifle. An Overshield can be found in front of the Prophet statue.
Another interesting feature is the addition of doors; the doors make you feel like you're in the levels Gravemind and High Charity. It is pretty rare to find classic doors in a multiplayer level like this; Gemini is in fact the only multiplayer map that features these doors.
The statue of the Prophet in about the middle of the map is probably a founder of the Covenant and what appears to be a natural tree. Outside, the map features five Covenant Phantom docks and what appears to be another natural tree. In the background behind the Phantom docks you can see the Forerunner Dreadnought that the Prophet of Truth used on the Halo 2 level High Charity to get to Earth, this is the only multiplayer map to show the Dreadnought.
- Lower Level
- Upper Level
- Gemini is one of the twelve signs of the Zodiac and is represented by twins.
- Some believe the symbolism of the Prophet and the Halo ring represents the Prophets' role as providers of the Holy Rings to the Covenant.
- Gemini can be spotted in Campaign mode in Halo 2. On the level Gravemind, when you exit the High Council Chamber and you get near where Thel 'Vadamee was tortured, look to the left, and in between the two giant towers with the eye-shaped purple design, you will see a smaller tower with the exact shape as the Gemini map.
- There are two spires that appear in the levels Gravemind and High Charity, but the player is unable to destroy their bases or knock them over.
- This is one of only two maps in the Halo trilogy to have blue teleporters instead of green, the other map being Cold Storage.
- Outside looking down over the edge of the platform it is possible for the player to get down and run around on the spikes far below.
- The level itself is a spiritual successor to the netmap "Duality" from Marathon 2: Durandal.
- Gemini is the only multiplayer level in the Halo Trilogy in which you can see the Forerunner Dreadnought.
- The tree in the center of the map bears a striking resemblance to the tree seen in the multiplayer level Warlock and the Halo 2 campaign levels Delta Halo and Regret. It is unclear, however, if the tree in Gemini and the trees on Delta Halo are the same species or not.