With Petrino's permission, Lapitus managed to quickly take over the mansion guards.
The numerous small squads scattered all around the huge building that were once led by captains loyal to Kalidus were quickly dismissed and told to go home for the day, as Lapitus's men took effective control of the men under them.
While the guards that were originally assigned to protect the main hall room, the place where all the events would take place, were all dismissed or relocated to other parts of the mansion, their places filled by Lapitus's own, trustworthy men.
These men were trained veterans who were going to be the ones who were going to do the butchering.
As for the higher level posts that had become empty, particularly those held by those ten officers, such as the gate controls, well Lapitus's co-conspirators were able to take control of them too, usually saying something along the lines of this,