Strange...

[randompeep]

The mysteries of Bigger Ben are numerous. What does the tower contain? What do the tombstones mean?

This is yet another one, involving the Ice Chamber and some Jr. Yetis.

Every single time you kill a Jr. Yeti on this entrance platform, it is guaranteed to transform.
http://i329.photobucket.com/albums/l369/Elvarg27/maplestory%20pics/Maple0008-1.jpg
http://i329.photobucket.com/albums/l369/Elvarg27/maplestory%20pics/Maple0009-1.jpg
Coincidence, maybe? Well, it would, if it weren't for these.
http://i329.photobucket.com/albums/l369/Elvarg27/maplestory%20pics/Maple0011.jpg
(note the horn...)
http://i329.photobucket.com/albums/l369/Elvarg27/maplestory%20pics/Maple0007.jpg
http://i329.photobucket.com/albums/l369/Elvarg27/maplestory%20pics/Maple0010-1.jpg
Now is it a coincidence? (this last one is not hacking) (note: all SSs were taken within 30 minutes.)
It may not be great, but I thought it was worth posting. :)

[Blankout]

That's where the transforming Jr. Yeti is. :)

It's fun to kill if you're collecting Hyper Glyphs here.

[randompeep]

Is that the only place where they transform?

[Blankout]

Is that the only place where they transform?

I think so. I haven't seen another that transforms.

[Rayquaza2233]

It is, no other one transforms.