The grammatically correct sentence is: "May this festive season bring you happiness and prosperity."
The word "bring" is the correct form of the verb to use after "May" in this context. When using "May" to express a wish or a hope, the following verb should be in its base form (infinitive form) without the "s" that is typically added for the third person singular (he, she, it) in the present tense.
So, it should be "bring" (base form) instead of "brings" (present tense with 's').
Example:
- May she find success in her new job. (correct)
- May she finds success in her new job. (incorrect)
In your original sentence, "May this festive season bring you happiness and prosperity," the verb "bring" is in the correct base form, making it grammatically accurate.