What Iron Brigade is
Iron Brigade is a tower defense shooter from Double Fine Productions. You pilot a mech called a trench, walk it around the battlefield, and shoot at waves of Monovision machines yourself while also dropping stationary defenses to cover the ground you can't be everywhere on. The mix of aiming and building is the whole point: your own guns do a lot of the work, and the turrets you place shape where the enemy gets stopped. The tone is comedic sci-fi, with the Monovision menace played for laughs as much as for threat.
Playing it with friends
Online co-op lets you march side by side with allies from around the world. Each player brings their own mech and their own set of defenses, so a group can split responsibilities across the map: some hold a lane with mobile firepower, others lay down turrets where the pressure is heaviest. Coordinating loadouts matters, since the trench you customize decides what you can personally handle and what you need your defenses to cover. Fighting through Europe, Africa, and the Pacific gives the group a long shared campaign to work through together.
Loadouts and customization
You can customize your trench with thousands of possible loadouts, which means the same mech can be built in very different ways depending on what a mission demands. Expect to spend time in the menus swapping weapons and equipment between runs, and expect your build to change as you pick up new gear. Since everyone in the group builds separately, a balanced team usually comes from talking through what each person is bringing rather than everyone running the same setup.
What to know before starting
The base game covers the Monovision threat across Europe, Africa, and The Pacific. Beyond that sits Iron Brigade: Rise of the Martian Bear, an expansion with a Martian campaign, over 80 new pieces of loot, 4 defense missions, 2 survival missions, and a Boss mission, where you face Vlad's new Monovision Constructs. Check that your group has the same content installed before you plan a session around it. The game blends third-person shooting with tower defense planning, so if your group only wants to run and gun, or only wants to place towers and watch, part of the design will go unused.