Breakdown of Dicen que el grafiti tiene una maldición.
tener
to have
una
a, an (feminine)
que
that / than
decir
to say, to tell
Questions & Answers about Dicen que el grafiti tiene una maldición.
Who exactly is saying this if there is no subject like ellos before dicen?
This is an impersonal use of the third-person plural. By using dicen without a subject pronoun, it translates to a general "people say," "they say," or "it is said." If you explicitly added ellos, it would mean a specific group of people is saying it, rather than just a general rumor.
Can I drop the word que and just say "Dicen el grafiti...", since we often drop "that" in English?
No, you can't drop it. In English, we can say "They say [that] the graffiti...", but in Spanish, the conjunction que is strictly required to connect the two parts of the sentence.
Why is grafiti spelled with only one 'f' and one 't' here?