It was the crumbler set
Head Smash
Iron Head
Shadow Sneak
Sword's Dance
With life orb.
This was the set that adapted to the mandibuzz anti-aegi meta where he would just lure and nuke something that comes in. They didn't bother running king's shield because he would just swap in, stat check something, then either clean up with shadow sneak or just nuke a check out of existance.
Sometimes they'd swap iron head or sword's dance for sacred sword, flash cannon, or shadow ball just to fuck with tanks and bisharp.