The Party needs to recover a stolen chariot filled with goods from a large band of kobolds. However, when they arrive, it turns out that all the kobolds have been killed by three ogres. One ogre is dead and two are alive, but wounded. They therefore have lower health than the printed statblocks. The party needs to engage them to recover the chariot. Should I lower their CR? If so, how can I determine how much to lower it by?
How does reducing a monster's hit points affect its CR?