Despite the risks and effects that this plan has, Keon still had Cain to be the one that would do it. Of anyone that Keon knows, no, out of all people in the Empire, in terms of fighting prowess, Cain is at the very top
There is no one else suited to do this job aside from Cain. Even Keon is far from being the first choice
Keon is also good at using a sword but there are people that are still better than him like the Dukes of Ybra and Ronchelot
Keon's strongest suit is after all his magic that would take a longer time to use rather than just using a sword to stab Lawrence to death
This situation was completely unexpected to everyone present here to watch Keon's execution and they were not able to react fast enough when Cain's sword already stabbed Lawrence in his heart, undoubtedly piercing him in the chest
Before anyone could move, a bright blue pillar of mana suddenly appeared, drawing all of their attention toward it