https://www.gamespot.com/articles/the-divisions-biggest-ever-free-update-out-now-fre/1100-6455395/

As part of its ongoing support for The Division, Ubisoft today launched the game's biggest free update ever, while the company also announced sales and promotions around the multiplayer shooter. Starting with the update, 1.8 AKA "Resistance" is out now on PlayStation 4, Xbox One, and PC. It adds a new area to the map, West Side Pier, which includes new activities such as the Resistance and Skirmish modes.

Resistance is a PvE mode in which the enemy factions team up (they have never done that before) to collectively fight against players in what sounds like a Horde-style, wave-based mode. In teams of four, your objective is simply to stay alive as long as possible. When killed, enemies provide resources that you can use to firm up your defenses and more.