# Change Skill Set Each Mongen can prepare a certain number of skills at the same time. However, Mongen can only use one of them in each battle. This skill is called Active Skill The number of skills that can be prepared and the rarity of the skill depends on the rarity of the part in Mongen's DNA. User can change the skill mongen is using by using Skill Stones The list and icons of Skill Stones are as follows:
IconItemDescription
Normal StoneWhen used, randomly choose one of prepared Basic Skill (exclude current Active Skill) as Active skill.
Reroll StoneWhen used, chosen prepared Basic Skill is replace by the new skill that is not in list of prepared skill randomly.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.
Normal AmethystWhen used, randomly choose one of prepared Ultimate Skill (exclude current Active Skill) as Active skill.
Reroll AmethystWhen used, chosen prepared Ultimate Skill is replace by the new skill that is not in list of prepared skill randomly.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.
Common Elective StoneWhen used, chosen prepared Basic Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0.
Uncommon Elective StoneWhen used, chosen prepared Basic Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0.
Rare Elective StoneWhen used, chosen prepared Basic Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0.
Epic Elective StoneWhen used, chosen prepared Basic Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0.
Legendary Elective StoneWhen used, chosen prepared Basic Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0
Common Elective AmethystWhen used, chosen prepared Ultimate Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0.
Uncommon Elective AmethystWhen used, chosen prepared Ultimate Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0.
Rare Elective AmethystWhen used, chosen prepared Ultimate Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0.
Epic Elective AmethystWhen used, chosen prepared Ultimate Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0.
Legendary Elective AmethystWhen used, chosen prepared Ultimate Skill is replace by the new skill that is not in list of prepared skill by your choice.

If Active Skill is chosen, the new replaced skill will be set as Active Skill.

Note: You cannot choose skill that have spawn rate equal to 0.