I'm always appreciative of when a game gives you an extra special reward for achieving 100% completion (or it's version of that) of it. Was wondering what other people considered some game's best 100% rewards?
The best one I can think of is Sonic Adventure 2's 3D remake of Greenhill for getting 180 emblems. It's extremely frustrating thing to do but playing through the first ever Sonic level in glorious 3D made it worth it.
On the other hand, when a game offers only a harder mode as a reward it usually bores me. Few games are worth the effort of another playthrough after already beating the original 100%, though there are exceptions.