For the first two stages, we can defeat Lesmes and Sleeping Infant by attacking them after they perform an attack (i.e. when Sleeping Infanta runs out of spikes or when Lesmes slams his coffin into the ground). For Lesmes's third stage, we should prioritize knocking our Sleeping Infanta with a flaming Veredicto for extra damage so we only have to worry about dodging Lesmes for the rest of the battle.