This egg was only available in Egg Cave's Cash Shop Park for October 2012.
Rencup eggs are ice cold for the first two weeks. After that, they start to warm. However, do not handle a Rencup egg while it's ice cold, because it causes permanent freezing burns that cannot be healed.
Rencups are ice cold dragons that can freeze anything with their breath. Rencup ice has fascinated researchers as of late, because Rencup ice lasts twice as long as normal ice, even in hotter temperatures. To this day, nobody know why Rencup ice possesses this strange property.
Overall, Rencups are friendly dragons. Just know that, if you're breathed upon by a Rencup, you're likely to never thaw.