Dario Delacio is the first actor to play the role of Doomsday in a live action role. Doomsday has been portrayed before on television but only in a voice role on the Justice League animated series, follow up series Justice League Unlimited and the video game Justice League Heroes. Sam Witwer played the role of Doomsday's human counterpart, Davis Bloome.
- Dario is 6' 8" (2.03 m) tall.
- In all Smallville episodes in which he appears, Dario is credited as "Dario De Iaco", presumably due to misunderstandings as the lowercase "L" and upper-case "i" look similar.
- In four of his five credits, the capitalisation of Dario's name appears in the normal Smallville style of having all letters capital, and reads "DARIO DE IACO" (see above for the discrepancy with the name itself). However, in the episode "Infamous" alone, he is credited as "DARIO De IACO". This is a very unusual occurrence - to see a lowercase character in Smallville credits.
Dario has portrayed Doomsday in the following Smallville episodes.