At first glance, there’s nothing particularly special about the half-page above. Looks familiar, clearly drawn by Yoann in his current Spirou style, it’s from one of his albums, right? … But wait! Which album? Zorglub and Martin only appear together in the one-shot, but that was drawn in a completely different style. What’s going on?
It turns out that it is in fact a redrawn version of this half-page from Les géants pétrifiés (“The Petrified Giants”):
Why would Yoann redraw half a page from an earlier album? I have no idea. The only idea I can think of is that it was in preparation for having Martin appear in Le groom de Sniper Alley (Spirou & Fantasio #54, “The Sniper Alley Bellhop”), to work out how the character would fit in the more classical style. But that’s just a wild guess. Maybe it was just for fun. Or maybe Yoann has started drawing fanart of his own work!