The Legend of Zelda: Link's Awakening is a classic Game Boy Zelda adventure. Link must travel across the dream world of Koholint Island, collecting the 8 Instruments to wake the Wind Fish and go home after a terrible shipwreck.
bobmario511 (the author), however, decided collecting instruments for a one-man band was a waste of time, so he skipped all of that and went straight to the Wind Fish (with a pesky boss battle in the middle).
The author improved the run by 00:00.17 seconds merely by delaying the third screen warp by one frame. Doing this causes the object on the screen to disappear, reducing the lag by 15 frames. After encountering 5 frames of seemingly unavoidable additional lag, the author produced a run with a net improvement of 10 frames. See the author's notes for more details.
If you liked this, be sure to also check out the Game Boy Color version (DX), which completes all the dungeons.