As you might expect, damage is the mechanism by which actors' HP is reduced to zero. Maximizing the damage you deal, while minimizing that which you receive, is key to a successful run.
Not all damage is treated equal, however; it has types, which influence how effective your weapons are against your various foes. Damage types in Jupiter Hell include: impact, slash, pierce, plasma, fire, toxin and EMP. Some of these types are exclusive to enemies.
List of damage types[]
Impact[]
Impact is the "default" damage type; the majority of guns you will encounter deal Impact damage. It has no special properties, and deals full damage to armor durability and hit points.
For example, a player with armor protection of 2 is hit by an attack dealing 16 impact damage. First the durability of the player's armor would be reduced by 16. Then the armor protection of 2 would reduce the overall damage to the player's hit point total to 14.
Slash[]
Slash weapons typically deal high amounts of damage, but is significantly mitigated by armor. It is usually dealt by area-of-effect weapons like shotguns and rocket launchers, as well as many melee weapons. It causes a typed weapon to deal half its rated damage to armor durability, as well as treating armor as having double its protection for the purposes of calculating damage resistance. Additionally, typed weapons deal half damage to Mechanical enemies.
For example, a player with armor protection of 4 is hit by an attack dealing 60 slash damage. First, the durability of the player's armor would be reduced by 30. Then, the armor protection would be counted as 8, reducing the overall damage to the player's hit points to 52.
Plasma[]
Plasma is effective at piercing armor and is common later in the game. Typed weapons treat armor as having half its protection for the purposes of calculating damage resistance.
For example, a player with armor protection of 6 is hit by an attack dealing 12 plasma damage. First the durability of the armor would be reduced by 12. Then the armor protection would be counted as 3, reducing the overall damage to the player's hit points to 9.
Pierce[]
Pierce one of the most powerful damage types in the game. It causes a typed weapon to deal double its rated damage to armor durability, as well as treating armor as having half its protection for the purposes of calculating damage resistance. Additionally, typed weapons deal double damage to Mechanical enemies.
For example, a player with armor protection of 8 is hit by an attack dealing 10 pierce damage. First the durability of the player's armor would be reduced by 20. Then the armor protection would be counted as 4, reducing the overall damage to the player's hit points to 6.
Punch[]
Punch works the same way as impact, but cannot damage armor and can be reduced to 0 damage by armor.
Fire[]
Type weapons and abilities, including barrel explosions, deal half damage to mechanical enemies.
Toxin[]
Type weapons and abilities, including barrel explosions, deal no damage to mechanical enemies.
Acid[]
Type weapons and abilities, including barrel explosions, are strongly affected by, and strongly affect armor. Armor is treated as five times its effective value, but also suffers three times as much damage from Acid.
For example, a player with armor protection of 3 is hit with an attack dealing 15 acid damage. First, the durability of the player's armor would be reduced by 45(!). Then the armor protection would be counted as 15, reducing the damage to the player's hit points to zero.
EMP[]
Type weapons and abilities deals no damage to non-mechanical enemies.