Tony's Charjabug
Tony has a shiny Charjabug that he interacts with fondly, much like his hand-made robot friends Dum-E and U back home. As it is a battery Pokemon, he is able to use it to add a charge to his armor instead of drawing on power from his arc reactor, which is the source of his blood poisoning. The idea being that this will help him stick around longer. It's also a companion that he can unload on who won't talk back or question his life choices. It's name is 9-Volt.