I don't think this is a game breaking bug, but it's too goofy lmao.
I think the attack speed value goes below 0 after selling the third or fourth item, so game gives you max attack speed instead of whatever value below 0.

Wait I forgot this is a YouTube video, let me put it in a language you can understand:
WOW BROKEN BUG, 10 AS NEEKO, KILL BARON IN 2 SECONDS, RITO NERF PLZ!!!1!

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