>>56391145(still me)One thing I have seen done with Competitive Wigglytuff in VGC formats (not actual competition mind you) is teaching it Hyper Beam.
Why Hyper Beam, you ask? Because this actually can guarantee OHKO and the Wigglytuff player doesn't give a fuck about keeping it alive after scoring the shot. It's still not the best mon for this, but there's barely any difference at this point if you only want to blast once and fuck off.