Relics of the Past

Relics of the Past is the first DLC for Monolith, released on December 25th, 2019. It adds a substantial amount of content to the base game, as well as redefining and tweaking many existing systems. Some notable changes include the addition of Cartridges, two new ships, two new floors, and the Looping mechanic. This is far from everything that was added. A more detailed (not comprehensive) list of changes can be found below.

List of Changes
Mechanics & Elements
 * Added A.B. and Skully
 * Added Looping
 * Added Hacking
 * Added Carts
 * Added Council Blessings
 * Added option to save a run report
 * Added difficulty choice
 * Added Kleines death tips
 * Added Shields
 * Added Lootcrates
 * Added mid-run saves

Facility
 * Added Temple floor
 * Added Nowhere floor
 * Added Reliquary room
 * Added Arcade room
 * Added Breachstone and Breaches
 * Added shortcut rooms
 * Added Unique weapon shops
 * More types of blocks and traps
 * More vaults
 * More Renegade deals
 * More rooms for all floors
 * More minibosses and enemies

Upgrades
 * Added Upgrade descriptions
 * Added Quickening and Scrap Runner
 * Artifact spawns blessed weapons, and rarely, Uniques
 * Extra Pow further clarifies bomb regeneration
 * Plating now increases both current and Max HP
 * Voltaic improved and renamed "Weatherproof"

Weapons
 * Added Unique weapons
 * Added blessed and cursed weapons
 * More keywords
 * Thunderhead now always targets closest enemy
 * Vulcan damage slightly buffed

Enemies
 * Several enemies added

Special Entities
 * Added Warden, ChaosGod, Database
 * Added Trespasser and Microcore
 * Added Challengers
 * Added Grinder, Charlie, Fish, Nightmare
 * Overlord slightly nerfed

UI
 * Added second info screen
 * Added note indicating manual weapon scrap
 * Changed the sprite for HP parts
 * Damage display has base and effective damage
 * On map, some rooms use faded colors to indicate status
 * Clarified bomb regeneration mechanic

Lobby
 * Added Mirror with Reports and Practice
 * Added Painting
 * Added more music
 * Added Energy Bombs
 * Bestiary expanded, with improved portraits
 * Care Package cost reworked

Miscellaneous
 * Chaos ship no longer has infinite ammo
 * Anti-type keywords now also prevent revenge bullets
 * Multiplier max increased from 2.5 to 3.0
 * Non-Mild runs can have more than 1.0 multiplier
 * Added destructible bullets
 * Added a padlock icon below items that will not break upon leaving the room
 * Made keys not break upon leaving the room
 * Changed some bullet sprites
 * Run finish screen now includes lethality and difficulty icons

Upcoming Changes
Relics of the Past has an update planned for sometime in the future that will revamp the Looping system, add boss rushes, add a new ship, and revamp Skully, among other numerous additions.