Larger then Moon for sure, probably around the same size or larger then Old Russia. No (could be wrong on this one, but absoutely no proof). Campaign will around the already done 32 (the 32 already meets a mysterious character, travels all planets, and makes it into the Black Garden. Maybe 40?). Strikes will be similar sized: Fighting enemies, Challenge of sorts, Fighting enemies, Mini-Boss, Fighting enemies, Boss. Halo is not the same kind of Destiny "buzz", but I played Reach until it broke.