I've been a big fan of the Lego games for a while now – Lego Star Wars, Lego Indiana Jones and Lego Batman. They are all fairly simple games on the surface, yet can be challenging when you dig into them. My young son (who is now 9, but started playing the Star Wars game when he was 6 or 7) was able to play two player games with me, and contribute to winning (unlike some other games where he was just a burden due to his limited skills).
In Lego Batman, we easily managed to get about 85% of the game finished between us, just playing through the levels in Story Mode and then Free Play mode. Once we hit 85%, it became a concerted effort to collect everything and reach 100%; something we'd never quite managed with Star Wars or Indiana Jones. We played every level, became "True Hero/Villain" everywhere, rescued all the hostages, gathered all the post boxes and artefacts, and played the "special levels". Despite that, we were stuck at 98.8% and there were still some data items that weren't unlocked. I couldn't figure out why; there was nothing left to find, no levels left to play.
Turns out, according to various web searches, this is pretty common. I saw a lot of "98.8% complete – help!" items in forum posts, and many seemed frustrated by what folks were assuming was a bug or glitch. I was definitely in the "frustrated" bucket myself. However, I don't think it is a bug.
I went back at the weekend and replayed the "special levels" – Wayne's Manor and Arkham Asylum. I played Wayne's Manor (and due to some issues finding items), finished it in about 40 minutes. Nothing changed in my completion status. So I played it again, this time focussing on getting things done quickly. 19 minutes and a completed Wayne's Manor later, and suddenly I was at 99.4% complete. Hmm, 0.6% extra for completing the level quickly. Also, 0.6% shy of 100%.
Assuming that the elusive 0.6% could be gotten in the other "special level" by completing it quickly, I headed over to Arkham Asylum and zoomed through it as best I could. Imagine my joy when the final 50G message immediately popped up, and the completion percentage went up to 100%!
So, hopefully this post will help some of the other folks on the internet who have been frustrated by this situation. It isn't only about getting everything in the game, certain things need to be done quickly too.
[Oh, by the way, if anyone is reading this who can influence the right folks at the video game company, creating "Lego Back To The Future – The Video Game" would be completely AWESOME…]