If your whole team is Magic, You have to be extremely careful with Affinity changes.
The Clan Boss Affinity is Void from 100% health to 50% health.
When the Clan Boss Health drops below 50% health, He will change affinity.
The Clan Boss Affinity willl change to Spirit, Force, or Magic.
It will happen Randomly.
Force Affinity CB will make your whole team do reduced damage by 20% due to affinity disadvantage.
You will also do a further reduced amount of damage from weak hits.
Magic Affinity CB can reduce your teams ability to do debuffs effecitively.
The Magic Affinity CB does Decrease ACC debuff which can cause your team debuff to be resisted.
Spirit Affinity CB can mess up your heroes turn order.
The Spirit Affinity CB does Decrease SPD debuff which can cause heroes rotations to get thrown off.