Update: Respawn has shared the full list of patch notes, further detailing some of the changes in store for players in this update. CTF mode has introduced sudden death (so games no longer end in a tie); you can earn stars on each map in each primary game mode by posting a certain score; new graphic options are being added on PC; and load times are improved. You can get the full rundown here.

Original Story: Respawn promised it would show off Titanfall's "biggest update" ever today, and it looks like it's delivered. The main component of the upcoming update is a four-player co-op mode that sounds a lot like the Horde mode popularized by Gears of War 2. This marks the first time the game has offered a way to play that doesn't involve playing directly against other players.

In Frontier Defense, you and three other players are tasked with defending a point (on existing game maps) from waves of AI-controlled enemies. These enemies include new types not seen before; in addition to variations on Titans already in the game, AI enemies will be able to wield all weapons and grenade types, and Specters will have the ability to rodeo your Titan, much like other players can in traditional multiplayer. You'll also be seeing far more enemies than you're used to--the Rise map can have more than 200 at once, for example.

Between waves, there's a dash of tower defense games, as you'll be able to place sentry turrets to help you defend. The Guardian Chip perk for your Titan can be especially handy in Frontier Defense, as it allows your Titan to be more effectively used as another stationary defense. That becomes important because among the new types of enemy Titans are ones that bombard the point you're defending from afar, forcing players to spread out to take them down.

Deaths in the middle of a wave don't necessarily equal defeat; Respawn says it didn't want dying to be especially punitive, so you'll be able to come back to life (by flying in on a dropship that you can shoot from). If your entire team is taken out, you'll be able to continue, though doing so will hurt the star rating you're assigned based on your performance.

Two other modes are being introduced in this update, though neither is quite as substantial as Frontier Defense. One, Marked for Death Pro, is a twist on the existing Marked for Death mode, which makes it a single-elimination, round-based mode. The other is called Deadly Ground; it covers the ground of each map with a deadly fog that means players have to stick to the rooftops and walls when moving. You'll be able to play game types like Marked for Death and CTF in Deadly Ground.

Respawn also mentioned a new ranked play option that will let you rank up without resorting to the existing Regen system. More details are still being announced on the Respawn livestream, which you can watch here, and we'll report back when the developer offers full patch notes.

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