Okay, he should have asked about finding the crystals first before luring but he is going to take the bike crystal as a Leviathan lure since that is what the creature seems ti be snacking on.

“Great thinking, I should get the crystal from the bike then I can wave it at the creature in the face before swimming it away from the city,” Jamie replies as he glances at the crystal powering his fish bike.

He quickly swims towards it, taking it out of the bike and returning back to Luca, in the hopes that his suggestion of using the bike powering crystal can distract the Leviathan away.