Mass Effect 3 Guide: Act 1 Earth Walkthrough, Key Loot, and Early Decisions

This section of a Mass Effect 3 wiki guide focuses on the game’s opening stretch—what to pick up, where to go to find key items, how to get through the early combat without losing momentum, and which decisions matter for the direction of your run.

At the start of the story, Commander Shepard—freshly removed from duty due to their actions in Mass Effect 2—has to break free from Earth and move fast. The immediate goal is survival, but the bigger mission is stopping the Reapers from wiping out every sentient species across the galaxy. The catch is that every step forward carries a price, and one trip tied to Mars brings both something to hold onto and something painful to lose.

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For additional Mass Effect 3 support, the guide points readers toward several related pages, including updates for the Legendary Edition, general how-to guidance, key choices and their downstream consequences, a romance-focused guide, the main walkthrough, and coverage of side missions.

  • Legendary Edition Changes
  • How-To Guides
  • Key Choices and Consequences
  • Romance Guide
  • Walkthrough
  • Side Missions

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Top Guide Sections

  • Legendary Edition Changes
  • Game Basics
  • Tips and Tricks
  • How-To Guides

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Marcus Chen is a gaming journalist and industry reporter with more than 10 years of experience. He covers releases, announcements, and trends across PC, PlayStation, Xbox, and Nintendo, and keeps a close eye on the indie scene and esports. Previously an editor at several gaming publications, he now writes news, reviews, and breakdowns of major industry moments—from big showcases to updates on popular titles. His work is aimed at players who want a clear, fast read on what happened and why it matters.