Splat Zones is a mode in Splatoon's Ranked Battles. It unlocks once the player reaches level 10 in multiplayer. The goal is to hold a zone long enough to get the counter down to zero.
In Splat Zones, two teams battle for control of 1 or 2 zones. When they have control of all zones, a counter for their team starts going down. These matches go for 5 minutes. If the other team caps a zone, their counter starts and if there is a large enough difference, the player's team gets an additional timer though it will not detriment that team's score. This counter will have to be completed before continuing the main counter though. When a main counter hits zero, the match ends and Judd declares the winner by a complete whiteout of the bar.
If time runs out while the losing team is in control, the game goes into overtime, giving the losing a final chance to win. When the winning team regains control or the zones remain uncontrolled for 10 seconds, overtime ends and whoever had the lowest main counter is judged to be the winner.