Digital Plarail & Tomica DX (Deluxe)

...one question:
I saw it on the box, just wondering if you know what this is.

If I read it correctly, it's a limited edition train set that was attached to this edition. If you search for Digital Tomica and Plarail on Jauce, all of them currently are simple jewel disc cases. The fact that this one was in this massive box, suggests maybe it came with the train? Sadly, I did not get it, and I can't find any more details or photos of a golden D-51

It's not a set, it's a D51 with no tender, and it's not Plarail, maybe Tomica diecast?

Take a look here:
https://blueplastictracks.com/showthread...6#pid61786

and here:
https://order.mandarake.co.jp/order/deta...1083803200