Dancer Cat has very high health with no clear weaknesses (excluding Ubers), having a fast attack rate, extreme range, and insane damage. Power-stalling with 4 Meat-Shields is definitely required. His stats are magnified by 2x in Insane, rendering him almost immortal.
Ururun is effective against Dancer Cat, especially if she consecutively knocks him back many times in a row, but their difference in range is only 5, so she won't last long unless she knocks him back a lot. Bahamut can deal heavy damage to Dancer Cat. Li'l Nyandam can last longer due to his range, but he doesn't do much damage. Cyberpunk Cat can also be used. Their ability to slow Dancer Cat helps to keep him away from your attackers.