Chaos magic. Is it necessary?

First of all, when choosing magic, you need to know the basic principle: magic either helps to enhance the strengths of a faction or reduce its weaknesses. All factions fall under this principle, and even the skills of the Tribes of the East confirm this. Notice that for the Tribes of the East's Super ability, you need 2 types of magic: Chaos magic, which fully reveals their advantages, and Summoning magic, which mitigates their weaknesses (such as low HP and defense). If you look at the choice of magic from this perspective, it becomes easy to understand which magic is needed for which faction and which is not.