Of course, refining demons below level 9 is fine, as Gargamel's spiritual force is sufficient to support a large number.
If he refines too many above level 10, exceeding his current cultivation maximum, the sealed demons will inevitably retaliate, causing him to lose control.
With his current tenth-circle ordinary realm, he can seal up to 3 level 10 demons. After reaching ten-ring senior status, it might increase to around 6, ten-ring Perfection can reach 9, and under extreme circumstances, he should be able to seal 10! At each stage, the number of sealed demons should not exceed his own minor realm, as it may lead to retaliation.
The most impressive part is that he can selectively seal 10 different demons with distinct abilities, forming a perfect combination. The effect of this is greater than a simple 1+1.
Hence, Gargamel holds significant importance in the Blood Battle.
