I really like your game! Very interesting
The hints about attack and creation helped me figure out how to nearly beat level 2, i had 75% of the map and way more iron than them, but I died because i leveled up too much such that my iron went from positive one trillion to negative one trillion
A few things that might make it better:
Rename creation to 'solders per second', attack to 'training per soldier' and iron production to 'bank interest rate', and iron to 'money'. This would make it a little more intuitive.
Put all the rules in one place on the website or in an in-game help screen activateable using a button, or at least have an option to turn off the dialogs so that the player is not pestered over and over again in level 1.
Give details on how the iron exploitation works. The algorithm is not specified so it's unclear what leveling it up actually does.
It took me about 5 games to figure out that the costs are 2^(theNumber). Why not just write the cost in brackets as (2^theNumber = theTotalCost)?
Make a four kilobyte version! The great gameplay you've got here could make it a winning entry in the j4k comp :-)
Really cool game for including the economics factor. Nice job.