Auxiliary Chapter 3: Summoner's Essence
Summoners possess a unique type of mana known as Summoner's Essence, which exists in 7 levels:
7th-Level Summoner's Essence – Only possessed by the main leads and their ancestors
6th-Level Summoner's Essence – All other leads summoners
Key rules:
Summoner's Essence cannot be upgraded.
It determines how many levels of a creature can be unlocked.
It determines the summoning frequency:
7th-level: Can summon a 7th-level creature once per day
7th-level: Can summon a 6th-level creature twice per day
… and so on