Tier 2
Perfect blocks now activate a short regeneration effect on Steven
3 Blue Chroma, 2 Violet Chroma

Tier 3
A stronger shield dash that deals higher damage, double knockback, and a guaranteed LUCKY strike!
20 Violet Chroma, 3 Red Chroma

Tier 2
All perfect blocks now perform counter attacks and ricochets
6 Blue Chroma, 5 Violet Chroma

Tier 3
Connie's "Sword Storm" ability now breaks shields and applies a Defense Down effect to the target
10 Violet Chroma, 10 Yellow Chroma, 2 Orange Chroma

Tier 2
Unlocks the "Whammy" ability. Increases the effects of Greg's jams when used after tuning. (Resets if any jam is interrupted or expires)
5 Green Chroma, 2 Indigo Chroma, 2 Yellow Chroma

Tier 3
While jamming, manually activate one extra bonus pulse of the current jam
5 Indigo Chroma, 5 Blue Chroma, 5 Yellow Chroma, 5 Orange Chroma

Tier 2
All enemies outside of Amethyst's whip attack range take half damage from her attack
9 Indigo Chroma

Tier 3
Enemies are now guaranteed to drop a star point when defeated with Amethyst's basic attack.
20 Indigo Chroma, 10 Blue Chroma

Tier 2
Enemies are now guaranteed to drop a star point when defeated with Pearl's basic attack.
6 Blue Chroma, 3 Yellow Chroma

Tier 3
When getting a perfect strike against a target with 20% health or less, there's a 25% chance Pearl will instantly defeat them. Does not work on bosses.
10 Blue Chroma, 10 Yellow Chroma, 5 Violet Chroma

Tier 2
Garnet can now break Obsidian and also has a 5% chance to instant-K.O. small to medium sized enemies. Doesn't work on bosses.
1 Blue Chroma, 1 Red Chroma

Tier 3
Unlocks the "Super Combo" ability. For 5 Star Points, this combo allows the player several extra punches
5 Blue Chroma, 5 Red Chroma

Tier 2
Unlocks the Molten Core ability. For 3 Star Points, super charges all of Peridot's contraptions for 5 seconds
10 Green Chroma, 5 Yellow Chroma, 1 Orange Chroma

Tier 3
Reduces cost of Molten Core by 1 Star Point
20 Green Chroma, 10 Yellow Chroma

To fully upgrade all your weapons and get "Back in Bismuth" achievement, you will need a certain amount of Chromas. You can collect them by breaking the brightly colored crystals with Connie, Pearl, or Garnet (only characters that can break them).

Red: 9
You will find one Red Chroma on Strawberry Battlefield, but most of them are located in Bismuth's Forge.

Orange: 8
Again, you will find one in the secret area of Strawberry Battlefield before getting to Bismuth's Forge, where the main bulk of them are. When it comes to Red and Orange Chromas, you'll just have to be patient and progress the story.

Yellow: 45
Found in Beach City Woods and Bismuth's Forge. Unfortunately there aren't a lot of crystals for them, so you will need to farm! The chroma crystals reset after about an hour of real time, I think. While you're playing, it might be a good idea to warp to The Barn whenever an hour passes, go left into the woods until you find the chroma crystals, then jump down and run past the enemies to the area of South Trail where more yellow crystals are (you'll have to grow some trees to get there). The warp pad is nearby, so then you can just warp out. You will get about five Chromas for each run like that. Well, that's how I farmed them, anyway.

Green: 35
Found in Beach City Woods and Strawberry Battlefield. They're not that rare, just make sure to get them whenever you see green crystals, and you're golden.

Blue: 46
The most common type. You won't have any problem with this one. Just get them whenever you see them.

Indigo: 36
Slightly less common, but not as bad as yellow ones. Found in The Great North, you might need to farm them a little when you find a good spot, but it's nothing too bad.

Violet: 42
Slightly less common. Found nearby the secret entrance to Bismuth's Forge (you're gonna have to find them for your first upgrade anyway) and in The Great North.

I put all the total amounts here so you won't need to guess when you have enough.

There's already a guide on that! Go check it out: Weapon Schematic locations by O-range


I hope this helps someone!