There’s something magnetic about ancient alien tech just waiting to be cracked open. And in Mass Effect: Andromeda, that tech is Remnant. Towering monoliths. Glowing glyphs. Vaults that hum with forgotten power. But behind all the spectacle lies a layer of puzzles that still manage to baffle players—even in 2025.

Whether you're starting fresh or pushing for 100% completion, Andromeda Remnant decryption puzzles aren’t just a side activity—they're woven directly into the game’s exploration and story flow. This guide will walk you through everything: where to find them, how to solve them, and how to use Remnant Decryption Keys smartly without wasting them.

Let’s start with the basics: Remnant decryption puzzles are grid-based logic challenges that resemble sudoku-like puzzles . Each grid asks you to slot in alien glyphs under a simple rule—the aim is to not duplicate any glyph in a row, column, or designated block. If that sounds familiar, it should. These puzzles borrow the elegance of Sudoku and layer on visual complexity using Remnant symbols.

You’ll encounter these puzzles throughout the Heleus Cluster, from vaults on Eos to terminals on H-047c in the side mission The Remnant Tiller . Some puzzles are mandatory for main story progression, others appear as part of secondary objectives tied to side missions like Voeld: Restoring a World or Helping Havarl’s Scientists .

To attempt a puzzle, you’ll usually need to:

1. Scan the surrounding area using your scanner.
   The glyphs required for the puzzle are often located nearby on walls, pillars, or platforms. You’ll sometimes need to climb or solve environmental riddles just to find them.

2. Interact with the decryption console after collecting all nearby glyphs .
   The interface will pop up, giving you access to the puzzle grid.

3. Solve the puzzle based on logic.
   Your goal is simple: use each glyph only once in every row, column, and square block. No guesswork—just good pattern recognition.

4. Or use a Remnant Decryption Key if you're short on time or patience.
   These keys are precious, though, so reserve them for more complex puzzles like the Khi Tasira terminal in the story mission The Journey to Meridian , where combat and pressure spike dramatically.

🔳 Sudoku-Like Design

Most puzzles are 4x4 or 5x5 grids , though some vault puzzles are larger. The logic mirrors Sudoku: each glyph must be unique in its row, column, and sub-grid. The aim is to not duplicate any shape within those constraints.

🧠 Pattern Recognition

Once you've played through a few, you’ll start recognizing common glyph groupings. It helps to mentally map them—diamond-with-line, U-shaped arcs, triangle clusters. Knowing which ones you’ve used where makes manual solving much faster.

⌛ Time Pressure + Combat

Some puzzles are passive. Others come with a countdown or send defense bots after you if you make a mistake. These high-stress situations are why some players prefer using Remnant Decryption Keys —especially during deeper vault puzzles or missions like Healing Kadara’s Heart .

Here’s where you’ll encounter the most interesting Remnant puzzles across Andromeda:

• Scan the surrounding area for nearby glyphs . Use vertical traversal or jumps where needed—many glyphs are hidden on upper platforms or rotating pillars.

• Open the puzzle interface . Interact with the console once glyphs are scanned and recorded.

• Start with what you know . Focus on rows or blocks with the most glyphs already placed.

• Cross-reference each glyph placement with other rows and columns. If a glyph appears in the same line, you can’t use it there.

• Avoid duplicates . Remember, the aim is to not duplicate any glyph in its set.

• Use the “question marks” sparingly. These are blank spaces—don’t guess wildly. Think in patterns.

• Failing isn’t the end . If you make a mistake, defense bots may spawn. Finish the fight, then try again—or reload a save if you're in a hurry.

• Use a Remnant Decryption Key if you're pressed for time. Especially useful during high-stakes missions like The Journey to Meridian .

Remnant Decryption Keys are rare and best saved for:

• Time-sensitive puzzles

• Puzzles deep inside vaults, where backtracking is hard

• Situations where failed attempts trigger large-scale defense waves

• Puzzles in story-critical terminals like Khi Tasira or late-game vaults

You can earn keys by:

• Looting Remnant caches

• Completing certain vault missions

• Crafting at research stations once you have enough Remnant data

Some puzzles are optional—but worth the detour. Here are standouts you don’t want to skip:

• Fusion Mod of Adrenaline (Havarl)
  Found during a side route near Havarl’s vault. Completing this unlocks a powerful mod that auto-recharges your powers after melee kills.

• Vault Puzzle - Elaaden
  Deeper in the vault lies a multi-layer decryption that guards a rare armor mod and a hidden lore terminal.

• Derelict Ship Puzzle - Investigate the Remnant Derelict
  Found on Elaaden. Multiple glyph terminals, drone fights, and a high-tier loot chest await.

• H-047c Final Puzzle
  Located at the terminal during The Remnant Tiller mission. Short on space. High on pressure. Worth it for the loot cache.

It’s easy to underestimate how critical your scanner is in this game. But think of it like your torch in a classic role-playing game dungeon —it’s your way to make sense of an otherwise cryptic world.

Scan everything. Not just for glyphs, but for additional Remnant tech, lore tablets, and hidden data clusters. Even if you’re not chasing 100% completion, this will unlock mods, blueprints, and insights that directly improve your gameplay.

Remnant puzzles weren’t built to be filler—they’re meant to make you pause. Think. Observe. They pull you out of run-and-gun mode and drop you into a quiet, eerie space where patience and logic matter. They echo the best parts of classic puzzle games, but dressed in Mass Effect’s neon alien aesthetic.

They’re not just about doors and terminals—they're about earning your progress. And once you master them, you start to look at the whole game differently. Every glyph becomes a clue. Every vault, a riddle. And that’s what makes Andromeda Remnant Decryption Puzzles so memorable even years later.

So grab your scanner, find those glyphs, and crack the vault. The answers are waiting.