Combining Skill Cards allow you to obtain a random, potentially higher grade Skill Card than the ones you used.
When combining Skill Cards, you must select unequipped Skill Cards to fill all 6 empty slots. Then, you may select either Normal combine or Special combine. Normal combine is free, and the resulting grade will defer from materials used (but there is a chance to get lower rarity). The resulting skill card will be presented after combination.
Using Special combine will guarantee an outcome equal to a certain grade in the event that low rarity fodder cards are used to "re-roll" a high rarity card, and allows combining 6 Skill Cards of the same level to get Skill Card of a level higher. Also, it gives Luxury Points.
|2★ grade in all slots||★3 or higher guaranteed|
|Highest grade is 3★||★3 or higher guaranteed|
|Highest grade is 4★||★4 or higher guaranteed|
|Highest grade is 5★||★5 or higher guaranteed|
|3★ grade in all slots||★4 or higher guaranteed|
|4★ grade in all slots||★5 or higher guaranteed|
|5★ grade in all slots||★6 or higher guaranteed|
|Highest grade is 6★||5 Topaz||★6 or higher guaranteed|
The original cost of Special Combine was 100 gems, and it costed 250 gems for combining into 6★, and it costed 10 Topaz for rerolling 6★ cards. However, following an event, they were changed to cheaper costs until further announcement indefinitely.