Individual Levels
Individual Levels, shortened as "ILs," typically refer to single room "speedruns," where a player tries to achieve a personal best room time (from the frame of transitioning to the room to transitioning to the next room). They typically showcase high to top level Strategies, with the hardest ones being so precise that they are impractical for Single-Segment speedruns. Despite the challenge of some, many ILs showcase practical Strategies that can be implemented into speedruns.
Examples
Root Tunnel Traversal
This room traversal uses terrain that can be navigated relatively consistently and is limited to only controlling the stick and releasing B for Boost Ball.
Dynamo Works Wallcrawl
This Out of Bounds uses Standable Terrain with standard Jumping methodology as well as a method of transitioning to Workers Path that makes this strat very practical for the Echoes Any% Speedrun.
Impractical Gathering Hall SW
This Secret World climb involves using very small Standable Terrain and precise Slope Jumping, making it impractical for most speedruns.