Still does not allow you to safely kill peaceful monsters, though they will attack you. In the endgame, proximity to magic portals is sometimes revealed. Intelligent monsters do not include jellies, zombies, golems, and the like. You float above the ground, avoiding any pressure-sensitive traps below. You cannot go down stairs or interact in any way with items on the ground below.
Flight gives all the benefits of levitation with none of the drawbacks.
Luck is a variable, not an intrinsic. A cursed luckstone reduces it while a blessed or uncursed luckstone increases it. Anti-magic fields, teleportation traps, and polymorph traps have no effect. Poisoned darts and arrows do not do extra damage or kill you outright. Potions of sickness do not poison you.