Halo: Combat Evolved
Halo CE, also known as Halo 1, has a few major skips, but most of the tricks are smaller and involve manipulating spawns and optimizing combat. The AotCR bridge drop and the Keyes shield bump are the most essential tricks to learn, as they both skip major parts of levels. Otherwise, learn the route by watching the WR video and using goatrope's tutorial.
While Easy has a greater focus on efficient tricks, Legendary is heavily combat-intensive. You should start with Easy, and switch to Legendary if you want more emphasis on fighting.
Halo Runs record page: http://www.haloruns.com/records?lb=100 (click the timestamps for video links)
- The Pillar of Autumn (Halo CE)
- Halo (Halo CE)
- The Truth and Reconciliation
- The Silent Cartographer
- Assault on the Control Room
- 343 Guilty Spark
- The Library
- Two Betrayals
- The Maw
Turn the Warthog from left to right and exiting. If you time it properly, the rear-left tire of the Warthog should hit you, launching you into the air. It is used on Halo (Halo CE), where you can fling into the Forerunner complex much faster than walking into the tunnels.
You can also fling using a Ghost. Since Master Chief exits the Ghost on the right side in Halo CE, you have to turn from right to left.
By pressing Reload-Reload-Switch Weapon (XXY on console), you can have your secondary weapon out while your primary weapon reloads itself. You should hear the reloading noise while your secondary weapon is equipped.
To double-melee in Halo CE, press Melee-Grenade-Melee (BLB on console). You will be able to cancel the melee animation by throwing a grenade and melee again.