Heat Metal Spell
D&D Heat Metal Spell Description: Heat metal makes metal extremely warm. Unattended, nonmagical metal gets no saving throw. Magical metal is allowed a saving throw against the spell. An item in a creature's possession uses the creature's saving throw bonus unless its own is higher.
More on the Dungeons & Dragons Heat Metal Spell
This is a good spell to use when you are confronted by a lot of people in armor. Watching them jump around trying to get out of hot armour is very interesting to watch. I have also found this spell to be very useful in extreme climates like frozen areas. It helps the person stay warm and comfortable in a very cold area.