The corner of Echo's mouth quirks; whether it's because he interprets her meaning one way or not at all is left unclear. Since mischief takes the forefront, he just accepts it as it is.

"Some of us have yet to learn that," he replies with a seriousness that carries a subtle note of mirth. He still shows some concern, however, the helmet tilting again as he asks, "Are you experiencing any other side effects from that vial?"