Quite a charming little mini-game you've put together here, lovely little feat considering the time restraints.
The amount of weapons you can get via enemy drops is what astounded me the most, that's a selection and a half! And each weapon sapping your energy / health by a different amount was also a touch of genius as well.
I can really see this being something more, if the thought to expand it ever came about. Lots of potential with this one! As it is now, it's a fun little way to pass a bit of time but as soon as you find a balanced weapon that lets you smite your foes without also killing yourself you can wander through this train forever!
Anywho, it's a nice quaint little game that everyone should play at least once! Keep up the awesome work =)