The secondary weapon slot found in your inventory can now be equipped with special weapons found in various shops in different nations throughout the game. There are three main types of special weapons:

Stun - chance to stop the other player from attacking for each round of the duration

Poison - causes the victim to lose hp each round

Weaken - lowers one of the victim's stats by a percentage for a number of rounds

Special weapons will only equip in the secondary slot. Once you equip the special weapon, a setting appears where u select a number. This setting refers to how many hits with your regular weapon you want to make before using the special weapon. For example, a setting of 7 would indicate you will do 7 hits with your regular weapon and then hit once with the special weapon.