Daishain’s 5e D&D RPG Main Thread The Diplomat says...
Round 1: Cast Mage Armor on himself
Round 2: Get to the other side of the golem using Misty Step and, depending on what is on the other side, he will try to move down that hallway a bit
Round 3: Hit the golem with a lightning bolt or, if the hallway is occupied, hit whatever is there with a lightning bolt or fireball for an area of effect if needed. If the area is too open then he will misty step back to group's side and report.
Round 4: Zap the golem with whatever his most potent damage spells he has left *smile*.
Rather off topic, but...
Start of the school week so might not get to post until late in the day. Here are Poppo's possible actions.