If you read the terms, it tells you clear as day:
[quote:3l7r8dmo]Licensee may use the Licensed Content in up to 1 commercial projects. A commercial project is one defined as a Work for Distribution launched with the capability to generate revenue, or intention to generate revenue through the sale of, licensing of, or otherwise intend to generate revenue directly from the Work for Distribution. If Licensee wishes to use the Licensed Content in more than 1 commercial projects they will need to purchase an additional License or the Licensed Content at the exclusive price if one is available (c.4).
Licensee is permitted to use the Licensed Content in unlimited free projects. A Free Project is one defined as a Work For Distribution that generates zero revenue, has generated zero revenue and does not have the capability to generate revenue in any form.
Summary, if you plan on making money (or make money) then yes, it is 1 sprite pack per project.