The game also features the return of Combo Breakers, attacks that can interrupt an opponent's combo when executed properly, as well as the new addition of Counter Breakers, which can cancel out an opponent's Combo Breaker while leaving the character vulnerable if improperly performed. Season Two later added Stage Ultras, environmental finishing moves that can be triggered on specific stages. Like in previous titles, players can finish their opponent using an Ultra Combo, an automatic sequence of attacks that can only be used to end a match. The basic elements of combos are Openers, special attacks that start combos Auto-Doubles, button presses following special attacks that create automatic hit sequences Linkers, required to join several auto-doubles together Enders, a sequence which finalizes the combo with increased damage and Manuals, attacks chains entered outside of the traditional combo structure. The gameplay in Killer Instinct retains its traditional combo-based mechanics. Further information: Killer Instinct § Gameplay