Bareilles' Armor

You conjure a stylistic set of armor that protects you the more you need it. If you are already wearing armor, it transforms what you're wearing, and you retain its bonuses. For the duration, you add 1d4 to your saving throws, and gain a +1 bonus to your AC. When you are below half your hit point maximum, you instead add 1d6 to your saving throws, and gain a +3 bonus to your AC.