"What, you know about this?" Adam asked in an unsure voice.
He was surprised since he wanted to go to the training even before the whole situation with Osana and Twelve Branches.
The fact that Osana's wedding would be in three months was just a convenient time frame during which he could devote himself to training with Tron. It was possible because of their acquaintance and help from Damien, whom Tron would certainly not refuse.
Silvana did not inform Tron about The Rule of Power, as that was only one of the purposes of this training, but not the main reason why Adam came here.
Even after the battle against the Plague Reaper, Adam wanted to become stronger and realized that he was quite weak compared to such outstanding fighters.
So... when Tron suddenly mentioned The Rule of Power, it couldn't help but stump Adam.
Tron nodded with a calm face.