Acid Worm Skip (AWS)
Acid Worm Skip (AWS) is a major skip featured in a number of categories, including Any%, Any% Hard, All Major Upgrades, and 100% Hard. As the name implies, it allows you to skip fighting the Acid Worm either entirely or until later in the game. It saves roughly 90 seconds.
AWS is perhaps the most difficult trick in Any%. In categories with Power Grip, the standard strat is to grip the left 3 blocks and upon reaching the last one, place a bomb near the left edge and do a very tight bomb jump. There is a difficult in-room backup for all categories that involves HBJs, which loses less time than reloading the room entirely. In categories without Power Grip, HBJs are required to skip Acid Worm.
In categories that don't require HBJs, doing them as your primary start loses ~3.5-5.5 seconds.
This is a trick that kills a lot of runs so try to find the most consistent method for you.
Tutorial
Dragonfangs highlights all the major methods of performing Acid Worm Skip in this tutorial.
Strat References
All of these strats are referenced in dragonfangs's tutorial.
Comparisons
See the video description for the rough timings for each individual strat.
Standard 4 Bomb Method
16:40 in the video.
1 Bomb Method
19:30 in the video. https://www.twitch.tv/videos/219336982?t=0h19m30s
Samthedigital's Strat
Not as crazy as it looks, but requires some fast fingers. Independently rediscovered by CScottyW a few years later.
Pause Buffer
The time loss for this strat will vary depending on your setup and how many pauses you do. Roughly the same speed as performing an HBJ from the acid.
Jump Extend
16:30 in the video. Very difficult, not recommended if you're not super comfortable with it. It is possible to grip the left block from the left side and jump extend, but it's even more difficult than this method.