Armor of Ore

You draw ore from the earth, and shape it into a suit of natural armor for you. You can end this spell early as a bonus action. Until the spell ends, you gain the following benefits:

• You gain 25 temporary hit points. If any of these temporary hit points remain after the spell ends, they are lost.
• Your AC cannot be less than 17, regardless of what kind of armor you are wearing.
• Your size doubles in all dimensions. This growth causes your size to increase by one category - from Medium to Large, for example. If there isn't enough room for you to double your size, you attain the maximum possible side in the space available.
• You can add your spellcasting ability modifier to any Strength check or Strength saving throw you make.
• As an action, you can make two melee spell attacks with the stony appendages of your earthen armor, which have a reach of 10 ft. On a hit, the target takes bludgeoning damage equal to 2d10 + your spellcasting ability modifier. This damage is doubled if the target is an object or structure.