Hearing that, Ace's feeling was complicated. He was angry to be put in the dark by Mars all this time about his plan. Mars had just confessed that the reason he gave the lich's skill crystal to Geo was to make the child the secret weapon of the town, which made Ace feel that he had been cheated.
However, he then recalled that Mars had already told his doubt if Geo was too young for taking the skill. It was him who said that Geo was ready. So, although Mars didn't tell the truth, he had given him an indirect warning that by taking the skill crystal, Geo would have to do dangerous things.
And maybe what Mars had said was the truth. One of the reasons he gave it to his son was because he had great confidence in Ace. Whether it was his loyalty and his capability.
Ace didn't see any reason to be angry anymore. He wanted to accept the position right away.
