Tower Princess

For this you must complete the bonus objective in both bosses prior to the dragon (collect the 12 flowers and cook the pig) the hard part is not letting them get destroyed in the fight because yes if either the flowers or the pig get destroyed in the dragon boss you will have to retry the whole run. The strat i used was light knight and where you spawn in the fight just make sure you spend the whole fight moving against the outer wall never letting yourself or the boss attack close to or in the direction of the banquet and flowers. At least for me i failed 2 times before getting it. It will require patience. Also good to note is using the ghost or vampire while doing this run could help if you need the extra health id say use ghost as vampire requires you to hit the target with an aoe from up close before giving half a heart back. Whereas the ghost always gives 1 heart back upon using her ability