The Explorer's Key is useable item that is unlocked by default. When used, it instantly unlocks all chests within a certain radius. Golden chests can spawn in most levels, but are more likely to spawn in later ones. Progress until you find an Explorer's Key, then keep it until you find a golden chest. Use the key within range of that chest will earn the achievement, as well as the Captain's Brooch item.
Easy "Endless Voyager" trophy
Keycards only appear during the final level. They are used to open optional rooms to collect items and devices used against the final Boss. They can drop from enemies and "golden boxes" (not golden chests). Only four of them appear per run. Play through the final level, collecting everything, but do not use any keycards.
Easy "Finders Keepers" trophy
Play level 4 "Hive Cluster" and find the bloated survivor at the bottom right corner of the map.
Easy "Lizard Bait" trophy
Lemurians are the small purple enemies that appear in the first level. If you did not earn the achievement through natural progression, start a new game and simply keep playing the first level.
Easy "Macho" trophy
Collect the Golden Bomb item and bank $10,000 in the same level. The bomb will deal half the value of your money in damage.
Easy "Seasoned Wanderer" trophy
Monster Logs are the book-shaped items that occasionally drop from monsters and bosses under the Rainstorm and Monsoon difficulty settings. Collect fifteen of these logs across any number of playthroughs will earn the achievement and unlock the Huntress class.
Easy "Sleepin' With The..." trophy
Play level 3 "Sunken Tomb", and go to the bottom left corner. Knock the Whorls (purple crab-like creatures) off the ledges and into the abyss until the achievement is earned.
Easy "The Lone Survivor" trophy
Play under any difficulty setting as any class. Clear out the first level by activating the teleporter and killing the Boss and all enemies. However, do not use the teleporter to move on to the next level. Once the teleporter has been activated and the activation timer has ended, no further enemies will spawn. Allow the game to idle until the timer reaches forty minutes.
Various Characters
Complete the indicated task to unlock the corresponding character.
Character
How to unlock
Acrid
Defeat Acrid in Sunken tombs.
Bandit
Complete Stage 3 (Sunken Tomb, or Frozen Fundra)
Enforcer
Defeat the Magma Morm, Collosus, and the Wandering Vagrant.
Engineer
Purchase 40 Drones.
HAN-D
Open HAN-D's container on the USS Contact Light level.
Huntress
Collect 15 Monster logs
Mercenary
Complete the game five times.
Miner
Defeat the Direseeker in the Magma Barracks level.
Sniper
Complete the game.
Various Trophies
Complete the following tasks to unlock PlayStation 4 trophy rewards.
Trophy
How to unlock
Better Luck Next Time (Bronze)
Fail a shrine 3 times in a row.
Diamond Casket (Silver)
Bank 20,000 gold.
Don't Mind If I Do (Silver)
Unlock a golden chest with the Explorer's Key.
Endless Voyager (Silver)
Collect 4 Keycards.
Finders Keepers (Bronze)
Find the bloated survivor.
Lizard Bait (Bronze)
Defeat 20 lemurians in one playthrough.
Lucky Devil (Bronze)
Pass a shrine 4 times in a row.
Macho (Silver)
Deal 5000 damage in one shot.
Master Hunter (Bronze)
Kill the Magma Worm, Wandering Vagrant, and Colossus.
