Anyone seen a train around here? I did [Train has left the station]

Some say there was a birthday recently and some say they really like cake.
I however simply say; have a train!

So where will this train of mine take you? Well, climb aboard and see, for all I know it could be going To The Moon! (Lvl 3+)

Update: It seems the quiz was harder than I anticipated, so I added some hints. It wasn't meant to be hard, especially not since I probably put a too high level on the main prize.
Update 2: Even more hints and possible answers added.
Update 3: Here's a dusty bonus for your perusal =)
Update 4: Ok, so there is a lv6 This War of Mine waiting for you on the train.

All the giveaways has ended and the gifts has been sent.
Here's the solution with all accepted answers to the quiz if anyone's curious.

View attached image.