Watching Fenrir was interesting. The great wolf was excited like a little puppy and showed that quite clearly. He jumped through the Slipstream portal the moment it opened and traveled across the planetary systems like he had never seen them. In fact, that might be true. Fenrir had been sealed so long, he must have missed the creation of countless galaxies.
But while Michael let Fenrir play around, Jormungandr and Hel waited patiently. To be precise, Hel was the only patient one, whereas Jormungandr couldn't wait to reunite with his children.