As you play through each game mode, note where the major events and challenges fall, helping you stay better prepared next time you play. At the end of most chapters is a big event you must survive, and at the end of each setting is usually the most difficult challenge seen so far. Each chapter is it's own level, which is often begins with ease before getting progressively more difficult. All of them, however, are built on the same foundation: You have a setting, such as a mall, rainy town, or carnival, and there are 5 Chapters in each setting to survive. When playing L4D2, you can choose a variety of different modes. Understand the layout of a typical L4D2 level. They are good options in the early difficulties, and, with the exception of chainsaws, can be used infinitely.

Melee Weapons: Katanas, baseball bats, chainsaws, crowbars, and other melee weapons attack in a wide swath in front of you, often killing Infected instantly.

You should always try and have 2-3 Medkits, at a minimum, in your party.

Medkits: Medkits heal your character completely.

If you find another one on the ground, you can pick it up to dual wield them, effectively giving you double power, shots, and firing rate. Pistols are weak but accurate and, most importantly, have unlimited ammunition. On the first level, they sit on a table right next to the door. At the beginning of every level there are several Medkits, which are thick, rectangular red packs, and several weapons. Pick up the Medkit and nearby weapons in the opening location.

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