With the Reapers controlling most of the galaxy, recklessly scanning as you fly around like a child pretending to be an airplane is a great way to get noticed (and murdered) quickly. Knowing exactly where to scan will keep Reaper alertness down, and knowing beforehand what you’ll find is a great way to accumulate credits early on in the game.
Should the Reapers reach full alertness - and subsequently give chase - leave the system immediately. Reapers are initially slow but pick up speed at an alarming rate and will eventually catch up. Once the Reapers are alert in a system, you’ll have to complete one mission before it’s safe to return. However, knowing where to scan means you can dash in and out, even with the Reapers aware and on your tail.
As you’ll likely realize, not all clusters can be accessed as soon as the game begins. New clusters open up as the story progresses or side missions are completed. Others are not available until a specific quest, such as an N7 assignment, is given to you by Traynor. We’ve outlined exactly when each new cluster was made available to us during our playthrough, though it may vary for you depending on your path.
Assets in this guide are listed as they appear in the images from left to right. Locations with no planet at the center signify ship wreckages, which grant varying amounts of fuel upon investigation.
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