Titans has yet to have a proper crossover with another DC series, and an upcoming Arrowverse-adjacent show would be a much better option than the originally planned Crisis on Infinite Earth’s Titans heroes' appearance. Although the Titans did appear in the Crisis on Infinite Earth’s crossover, their role in the Arrowverse event was limited to blink-and-miss cameos. While that made Titans an official part of DC TV’s multiverse, more specifically the representative of Earth-9, no further connections between the show and the Arrowverse have then occurred.
The very conception of the Titans series has caused it to be separated from the rest of the Arrowverse. Unlike shows like Black Lightning and the recently canceled Batwoman - which were made for the CW and thus managed to crossover with other shows of the network more easily - Titans was envisioned as a streaming-exclusive series for the now-dissolved DC Universe streaming platform. Titans was supposed to be the DC Universe’s flagship show, and thus it had to have an overall look and budget that stood out from other DC shows. Although the DC Universe platform is now limited to comic books only, Titans remained as a streaming title, now an HBO Max original.
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When discussing possible crossovers with the Arrowverse, Titans' Nightwing actor Brenton Thwaites revealed that he declined an offer to have a proper role in the Crisis on Infinite Earths crossover event. For the actor, there was not really a story-related reason to connect Titans with the other shows, and thus it would not make sense to sacrifice all the things that make Titans different – not necessarily better or worse – only for a shocking, fun moment. However,
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