- Main article: Artifacts
Artifacts are items that are found in hidden areas of certain levels and can drastically change gameplay, making the game much more interesting and/or challenging. Artifacts can be toggled on or off on the player selection screen. Any combination of all 10 artifacts can be toggled on simultaneously. In co-op, players can pick up an artifact, even if they already own it, and it will unlock for all other players in the match.
Artifacts do not spawn every time a level is loaded. Sometimes, continuous play is required to try get an artifact to spawn. Finding artifacts normally requires the player to find a secret path within the level, or hitting sets of targets within a short period of time. Artifacts, once unlocked, can be found in structures called Artifact Gates.
Bug: In prefs.ini for the game, there settings for the most recent artifact and difficulty choices made in a game. There are Artifacts 0-9 listed, which correspond with 0-9 in save.ini indicating which artifacts are unlocked. However, prefs.ini, there is also an Artifact10=0 listing. Setting this to =1 here or in save.ini does not appear to affect the game in any way.
It is, however, possible to edit the Save file for the game to recieve all of these artifacts. There are 10 artifacts starting at artifact 0 and ending with artifact 9. To enable all of these artifacts you simply edit the save file to include the lines artifact0=1 through to artifact9=1. This makes the game believe you have encountered and collected each artifact respectively.
In order of appearance in "Character Select Menu" Edit
Enemies always spawn as elites.
Only one enemy type spawns per stage.
Lock a random skill every minute
Enemies explode on death.
Deal 500% damage, but have 10% health
Use items have a random effect.
Chests no longer spawn; monsters now drop items on death.
Items are no longer random. You can choose which items you want to purchase.
Characters move faster at low health
Imps invade the map every 10 minutes
Interesting Artifact Combinations Edit
Command + Sacrifice: Argued to be "the best" way to get your ideal item build as fast as possible. This is only true if massive amounts of farming are done early in the game, well past the point where all chests in a given level have been unlocked. However, in any other case, Command on its own works better. Chests, shrines, drones, etc. will all appear throughout the game, and are guaranteed even on early levels, whereas with Sacrifice it is possible to get very few items every map (sometimes just the Boss's drop). If players stack 56 Leaf Clover, as they presumably would anyway even with Sacrifice, more and more drops will appear from enemies as the game progresses into spawning more elites. This means that more items are guaranteed to be available at the start of a game, and then the Clover will increase later drops to also be more frequent than if Sacrifice were also on. Sacrifice will only be advantageous if significant farming is done in approximately the first two maps, before any clovers would reasonably be acquired.
All Artifacts: Not as hard as it sounds. While difficult due to the danger of Glass, Spite, and Spirit, Kin turns off all boss spawns. Still easy to get destroyed, especially by stacked Jellyfish mobs or when Ancient Wisps get rolled (they seem to spawn with no sound, and will fire immediately).
All Artifacts except Kin and Command: Arguably the hardest mode. Players are at the mercy of RNG regarding what Use items get rolled Enigma, which skills get disabled due to Distortion, and the random items due to lack of Command. If not careful, a character's escape skill will be locked at a critical moment, resulting in death. One somewhat nice thing is that matches will end very quickly if things start out badly, but otherwise huge momentum can be built and then it ends up difficult but very fun. In co-op, players must coordinate and share items for survive-ability. It is possible to beat this mode.
Origin + Time Keeper's Secret: Triggering the stopwatch while the Imp Vanguard is spawning will cause a loop wherein many Imp Vanguards will spawn instead of just one. Multiple players can chain their stopwatches together to spawn a huge amount of imps for free farming.