d20 Legend fo the 5 rings had a race here seem to want the bird to be - was it called Kenku? Anyway, it had absolutely superb flying abilities and was next to useless on adventures on the ground. This was a VERY BAD idea! Basically, gameplay got divided into 2 sphere, one where all players but the kenku could leave the table, and the other where the kenku could leave the table. Each group was so much better at their chosen movement that the others were more of a hindrance. Not fun. It might be simulationist (simulating what, exactly?) but was the opposite of heroic and fun.