Two set blocks, you mean, right? Yeah, there was Lorwyn Block Constructed and there was Shadowmoor Block Constructed. It's 310 cards. The standalones up through Onslaught are bigger by 40 cards, but Mirrodin, CoK, and Ravnica are smaller at 306 cards, while Lorwyn, Shadowmoor, and Shards of Alara are smaller still (and Time Spiral is much bigger, I'm guessing because of all the timeshifted cards). If it's an expansion to a standalone set, what's the standalone set?