Bolster the Dead

Choose up to four skeletons or zombies. They gain the following benefits: 

+10 maximum hit points 

+1 AC 

+1 to attack rolls 

Alternatively, you may target a single skeleton or zombie with the following benefits: 

+20 maximum hit points 

+2 AC 

+2 to attack rolls 

+2 to damage rolls 

+2 to all saving throws 

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, you may target 2 additional undead.