This article is about planet difficulty. For character difficulty modes, see Difficulty mode.
Difficulty (or threat level) is the characteristic of planets. Difficulty affects the types of monsters that appear on the planet - for instance, Extreme planets usually have fire-related monsters - and the amount of hitpoints and damage they have. Difficulty also affects the types of blocks, biomes and dungeons that appear on it: the higher the difficulty, the harder blocks become to harvest at surface level and/or deeper underground and the tougher the guards that spawn in dungeons become; as well as the type of loot that comes from chests. Certain ores and biomes can only appear at specific planet difficulty: coal; copper; iron; core fragments; and diamond ores can appear on all planet difficulties, and biomes depend on the difficulty of the planet (for example, Risky planets have radioactive biomes like Jungle, Toxic and Alien). Villages appear at Moderate threat level planets or less: some appear at certain difficulty and/or planet enviroment type, such as Glitch villages.
A planet's difficulty is generally determined by it's star (for more information, see Stars). Here is a list of difficulties from least to most:
|Unknown (Tier 0*)||Breathing EPP||月|
|無害 (Tier 1)||None||庭園, 不毛, 小惑星帯|
|ほとんど無害 (Tier 2)||None||砂漠, 森|
|やや危険 (Tier 3)||None||海, サバンナ, 雪|
|危険 (Tier 4)||Radiation EPP Upgrade||ジャングル, 放射性, Mutated|
|強烈 (Tier 5)||Heating EPP Upgrade||Frigid Ocean, 極寒, 真夜中|
|非常に危険 (Tier 6)||Cooling EPP Upgrade||火山, マグマ, Scorched|
- The Unknown threat level is meant to be ambiguous, in that no threat exists whatsoever until you acquire Erchius Fuel or bring some with you. It is actually registered in the game files as Tier 10, presumably to make the Erchius Ghost as threatening as it is intended to be, but this causes some very strange behaviour if you attempt to establish a colony on a moon, as this allows you to generate Tier 10 weapons, with their stats scaled up accordingly - well beyond what you are currently intended to be able to find.