Kritika: The White Knights/Gems

Gems can be sold or 'enhanced'. This is not the same type of enhancement that applies to items. Gem's 'Enhance' refers to combining to gems of the same type (color and level, e.g. Ruby +2) to make one higher level gem. This is a simple process and only requires two like gems and some gold. With a gem level of +5 or higher, enhance success rates begin to drop. If an enhance attempt fails, the second gem used will be destroyed.

All gems with +1 or above require that the character be level 10 or above.

Gem effectiveness is related to stat effectiveness. You should focus on maximizing your stats in this priority (this order also implies shows which gives the greatest amount of CP, e.g. Add'l Damage and Damage Reduction gives the biggest bonuses to CP):
 * Best gems
 * 1) Add'l Damage (Amethyst): CP is based on your ATK stat; since this gem's bonus multiplies your ATK in some way, the CP will increase proportionately as your base ATK increases.
 * 2) Damage Reduction (Peridot): CP is based on your level, possibly DEF, and an unknown multiplier.
 * 3) ATK (Ruby): gives a raw CP bonus that does not scale much.
 * 4) Critical Rate (Onyx): gives a raw CP bonus that does not scale much.
 * 5) HP (Topaz): gives a raw CP bonus that does not scale much.
 * 6) MP (Sapphire): gives a raw CP bonus that does not scale much.
 * 7) DEF (Emerald): gives a raw CP bonus that does not scale much.

Gems give CP based on the enhance level of the gem, plus a multiplicative bonus possibly based on your level or base stat. Since the CP of, say, a Sapphire, increases with your level, and its bonus is not multiplicative like a Amethyst, then the CP calculation formula must be based on something else. For example, it could actually based on your total stats, rather than just the bonus of each individual item (which would make it easier to calculate). Note that the CP values below may show a range. This is because they were re-tested with different stats to produce a different CP difference. The thing to keep in mind is the difference between grades. E.g. the difference between grades 6 and 7 is often the same as 1 to 2. Thus, if you have two Amethysts equipped, it is best to wait until a third gem of the same enhance level can be formed before enhancing. This way, you will not lower your stat bonus. For example, if you have two level 5 Sapphires, you will get +5356 MP, but if you upgrade one to a +6, and you only have another +3 or lower, your total will go down to 5061 or lower. If you had a 4 and a 6, you would be slightly higher than than two fives (this is the threshold for when you should enhance).
 * CP calculation

Gem types
🇨🇴

Amethyst
Add'l damage +%
 * +0: 4.00%
 * +1: 4.50%
 * +2: 5.00%
 * +3: 5.50%
 * +4: 6.00%
 * +5: 6.50%
 * +6: 7.00%
 * +7: 7.50%
 * +8: 8.00%
 * +9: 8.50%

🇨🇴

Emerald
DEF +
 * +0: 244
 * +1: 378
 * +2: 470
 * +3: 585
 * +4: 729
 * +5: 907
 * +6: 1,129
 * +7: 1,378
 * +8: 1,681
 * +9: 2,093

🇨🇴

Onyx
Critical Rate + 🇨🇴
 * +0: 713
 * +1: 1,105
 * +2: 1,368
 * +3: 1,711
 * +4: 2,124
 * +5: 2,645
 * +6: 3,294
 * +7: 4,014
 * +8: 4,905

🇨🇴

Peridot
Damage Reduce +%
 * +0: 4.00%
 * +1: 4.50%
 * +2: 5.00%
 * +3: 5.50%
 * +4: 6.00%
 * +5: 6.50%
 * +6: 7.00%
 * +7: 7.50%
 * +8: 8.00%
 * +9: 8.50%

🇨🇴

Ruby
ATK +
 * +0: 300
 * +1: 465
 * +2: 579
 * +3: 722
 * +4: 900
 * +5: 1,119
 * +6: 1,395
 * +7: 1,701
 * +8: 2,079
 * +9: 2,586

🇨🇴

Sapphire
MP + 🇨🇴
 * +0: 720
 * +1: 1,116
 * +2: 1,389
 * +3: 1,728
 * +4: 2,145
 * +5: 2,678
 * +6: 3,333
 * +7: 4,068
 * +8: 4,960
 * +9: 6,177

Topaz
HP +
 * +0: 629
 * +1: 1,484
 * +2: 2,157
 * +3: 3,119
 * +4: 4,585
 * +5: 6,648
 * +6: 10,026
 * +7: 12,378
 * +8: 15,819
 * +9: 20,788