DMG里关于5级法师职业上古红龙的段落
Depending on the monster and the number of class
levels you add to it, its challenge rating might change
very little or increase dramatically. For example, a
werewolf that gains four barbarian levels is a much
greater threat than it was before. In contrast, the hit
points, spells, and other class features that an ancient
red dragon gains from five levels of wizard don't
increase its challenge rating.
MM里关于龙获得施法者能力的变体
VARIANT: D RAGO NS AS I NNATE SPELLCASTERS
Dragons are innately magical creatures that can master a few
spells as they age, using this variant.
A young or older dragon can innately cast a number of
spells equal to its Charisma modifier. Each spell can be cast
once per day, requiring no material components, and the
spell's level can be no higher than one-third the dragon's
challenge rating (rounded down) . The dragon's bonus to
hit with spell attacks is equal to its proficiency bonus+ its
Charisma bonus. The dragon's spell save DC equals 8 +its
proficiency bonus + its Charisma modifier.
24级上古红龙按照变体说法能放8环法术，法术数量是6个，每个法术一天可以放1次。
如果加5级法师职业提升CR的话，岂不是能放更多法术？