EDIT: Kaio would hold his action until the guards make a move. Since Rixon indicated that the guards could see them, I'm guessing the guards will implicate them in the crime and go after them. If that happens, Kaio will go behind them and try to hit them while they are distracted. For that, I am adding a Stealth roll.
Darting out of the shadows, Kaio rolls to the guards' very feet, drawing his sword as he does and slashing at Eddan's gut. As he does so, he brings his pommel up and attempts to connect with Pyter's jaw.
Rolls
Attack, Damage - (1d20+6, 1d6+4)
1d20+6 : (7) + 6 = 13
1d6+4 : (2) + 4 = 6
Unarmed Attack, Damage - (1d20+6, 1d4+4)
1d20+6 : (3) + 6 = 9
1d4+4 : (3) + 4 = 7
Stealth - (1d20+6)
(16) + 6 = 22