Best Halloween costume of the year goes to Ron Artest III ... who celebrated the holiday dressed as his ex-NBA star pops from his infamous Malice at the Palace brawl!!
Metta Sandiford-Artest's 25-year-old son -- a spitting image of the 2010 champ -- rocked a ripped No. 91 Pacers jersey for the occasion ... and shared several reference pics to make the connection for his followers, although none were needed.
15 years ago today, the Pacers and Pistons engaged in what was later named the "Malice at the Palace." pic.