This glitch should only happen in hackmons/glitchmons, it's a minor glitch that's just a video bug, I'm sure it can be fixed quickly.
When using Bounce/Dig/Dive/The rest of them, combined with truant, you loaf off on the attacking turn, but remain displayed as in the air/underground. This gives the image to the play they can't hit you, even when they can. Not sure how this works in the games as it's impossible due to Slaking's inability to learn two turn attacking moves. Replay:
Replay
This was a random battle, happened to run into a guy testing the same thing
When using Bounce/Dig/Dive/The rest of them, combined with truant, you loaf off on the attacking turn, but remain displayed as in the air/underground. This gives the image to the play they can't hit you, even when they can. Not sure how this works in the games as it's impossible due to Slaking's inability to learn two turn attacking moves. Replay:
Replay
This was a random battle, happened to run into a guy testing the same thing