Rollen appears on Liar Mountain in the Yo-kai World.
Yokai Watch 2
Rollen appears under cars in Breezy Hills.
Alternatively, Rollen can also be freed from the Crank-a-kai with a Green Coin in the present.
Receiving food (favorite): "Good eye!"
Receiving food (normal): "A decent roll!"
Freed from Crank-a-kai: "You won me my freedom! Might as well let it ride and be friends, no?"
This Yo-kai has a resemblance and a similar attack pattern of a Diemon, a monster from Dragon Quest VIII.
Though this series belongs to Enix (now Square-Enix), that game in particular was developed by Level-5, creator of Yo-kai Watch.
Rollen might be based on the youkai called tsurube-otoshi: appearing as a huge, grinning disembodied head, this creature likes to take residence in the thick of pine or kaya forests. It rolls around or suddenly drops from the treetops to startle passerbys or even prey on them, only to disappear back into the foliage just as quickly, laughing and taunting those below. These sudden motions, reminiscent of a bucket going up and down a well, are what this youkai owes its name to (meaning "bucket drop"). It is also believed to hurl stones or actual well buckets at its victims.
"Rollen" is a corruption of rolling. "Sainome Nyūdō" translates as "Dice Eyes Monk".