Can I do the Roto Loto at the end of the game?

Question

Im about to start my Ultra Moon play through and I've been wondering: If the Roto Loto can be done at certain points in the game's story, then could it be possible to do the Roto Loto after becoming champion and defeating Rainbow Rocket?

Answer 1

Yes.

Rotom will ask you random questions throughout the game- but that doesn't mean that's the only way to activate Roto Loto. Tapping Rotom on an area that isn't the map will give you a heart sometimes, and this heart may cue a Roto Loto, and when evolving Pokémon, Rotom may cue a picture to be taken. So, even post-game, you can use the Roto Loto! I've also had Rotom ask me questions even after defeating Rainbow Rocket. (But the questions aren't about in-game events, they're more "Whats your favorite time of day?" etc.,)

Source: Experience In-Game