You're missing a call to mysql_connect().

What's in opendb()?

Your condition is wrong for no income (60006 should be 6006), maybe that's the problem?

What's the expected result and what are you getting?

I don't really understand the question but there's a problem in the code: setcookie breaks header redirects unless you use output buffering.

The code seems to pick from a pool of three actual enemies, not types of enemies. When the player kills an enemy it will have 0 HP and will basically respawn as a corpse next time.

This line doesn't do what you think it does.

Echo your query and you should immediately see the problem ($limit).

You can use mysqli::$error to see what's going wrong: http://www.php.net/manual/en/mysqli.error.php If there's no error your query is returning zero rows. You can echo the variables (probably $password is the problem since username works in your other code fragment, perhaps you're forgetting to hash...

You're not fetching from the result set so $rowAID is null.

See http://www.php.net/manual/en/mysqli-stmt.fetch.php