I assume that glacio was another special frog that they released to players (it was not originally part of the game like Lanturnu). The design looks like a snow flake. Isn't that also the case with Tribus? That too was a special release. I know I received a Lanturnu while playing but it wasn't gifted to me. I think I read that it was released for Halloween. There are some that you will not find while playing because they are not part of the regular game. You get them from a gift or the developer does a special release.