Othermine

The Othermine is UnderMine 's roguelike mode. The northern room in the hub (referred to as "the Terminal") is unlocked when the player completes the 5 main zones and enters Nowhere at the end of their run. Giving The Gatekeeper inside the Terminal a will open the Othermine.

The peasant takes no gold or upgrades into or out of the Othermine with a few exceptions, such as Glasses. The player is dropped into the Antechamber at the beginning of each run where they receive some random upgrades and choose a relic, blessing, familiar, and curse.

Antechamber
At the start of every new location, the player enters the Antechamber. The Antechamber contains 2 relics, 2 blessings and 2 major curses. You must pick one of each to continue to the next floor. Upon picking up one, the other disappears.

The first Antechamber contains also 2 familiars which you pick one from, Valeen, at the top right corner and a big chest containing some upgrades.

Differences in gameplay

 * The Othermine consists of 3 floors per location and the Antechamber in between them.
 * The Order of locations is randomized, and the bosses do not have to appear in their usual zone.
 * You cannot go back up after defeating a boss.
 * Shops will have more items as you progress the Othermine. They may also be behind a rock-wall which needs to be bombed or locked.
 * More than 2 secret rooms and more than 1 crawl space may spawn naturally. There may be two shops (at least one will be blocked behind a wall) and two relic rooms (one requires 1 key, and the other 4 keys) spawning in a floor.
 * When bosses are defeated, the gold is dropped to the ground, and not in a gold chest, and they drop schematics, making Othermine a reliable way to gain those.