Leviathan Souls
Leviathan Souls are the semi-collection item of the game. There are only 25 in total, which is must less than the collection items of past games (crystals, moonstones, slime crystals, etc). You get a Leviathan Soul after you kill a Leviathan monster, which is like a mini-boss. They can be found on certain planets, and when you get near one, a health bar will appear near them and they will target on you and soon attack. Use your weapons to take the large enemy out, and then the Soul will fly to you. The Souls can be collected and then sold to the Smuggler, a character in Future Tools, for a decent amount of bolts. Collecting all of the Souls also will contribute to getting one Skill Point.