> What will Blizzard normally do if they accuse me pirating their assets?

Most likely, they will tell you: "shut it all down or we'll sue you into bankruptcy".

I recommend taking a look at http://opengameart.org for free (and legally free) placeholder art you can use instead, and changing any names ASAP to remove "Starcraft" and anything directly based on the unit names, etc. (Referencing Starcraft in the README or other such things should be fine, though.)

For example, "SpaceCombat" with "Troopers" and "Knights" and "Hordelings" and different art and music for everything would be fine, legally, even if the actual game mechanics were exactly the same (as long as it's your own code implementation of them).

Can they sue him if he's not in the US though? How is that legally possible?

Quick summary: it's a treaty that requires all member states to enforce their own copyright laws for works produced in other member states, and also establishes a minimum set of rights and minimum term lengths.

What do you think is special about the US? Copyright law exists everywhere.

exists, but perhaps not enforced.

Would couldn't they? They do business across most of the world already. Think about how many countries have people with WoW subscriptions.

Heck, just take a look at their list of offices: http://www.activisionblizzard.com/locations

Because US law doesn't apply to other countries.

Most countries have something approximately similar to the broad strokes of US copyright and trademark laws. Details are different, but "just using the same assets and names directly" is going to be a problem in pretty much any jurisdiction with enforced rule of law.

Just about every country in the world recognizes some form and variation of copyright and trademarks.

You do know that, right?

Likely they'll just send you legal threat and DMCA take down notice to both github and your hosting provider (if you don't use github pages of course).