"Thanks," Tony said, glancing at Steve and noting where his eyes were. It was strange to be desired for his blood. Then again, people wanted him for all sorts of other reasons. Why not his blood too? "It's the third version I've created," he said, lifting a tired arm to give the reactor a tap. "Go ahead, you're curious. Touch it. It's not going to hurt anything unless you rip it out of my chest." That made him think of Obi. His heart sank to his knees. "It's not fun to have a heart attack."