I have a lvl 30 timewarp and feed my stage 10 polar bear at approx 14:00 on a Friday, put down my battle boosts, 1-2 Dwarven Armor, plus 5 or 6 of the 2x2 boosts, whichever I have as I don't take account of what troops I might face as I always fight the same way, feed the bird and then whizz up...