Taking a random spell, I find Flames of Phlegethos. Its hit is
3d10 + Constitution modifier fire damage. Let's say the caster has a constitution score of 16, and he is level 2. This means his constitution modifier is +3 from his constitution score, and he has +1 from his half level.
Would his damage on this spell be
3d10 + 3 or would it be
3d10 + 4? The PHB doesn't seem to clarify this. Thanks!