Souvlaki Arni (Σουβλάκι Αρνί) is the lamb version, the traditional and more expensive option on a grill counter where pork is the everyday default. The price difference is the honest framing: lamb costs more to source than pork, so a stick of lamb souvlaki is the order someone makes deliberately, not the one they fall back on. What you are paying for is the meat itself. Lamb has a deeper, more mineral flavor than pork, and on a charcoal grill that character is the entire reason to choose it. Treated as the centerpiece rather than a substitution, it rewards a cook who respects the cut.
The build follows the same skewer-and-fire logic as any souvlaki, but lamb is less forgiving and the margin for error is narrower. Pieces should be cut evenly and kept a touch larger so the interior stays rosy while the outside takes char, because lamb pushed to well-done turns dry and the flavor flattens to tallow. They go onto the wooden skewer, then over charcoal hot enough to crust the surface quickly. Good execution shows as a deep brown exterior over meat still pink and juicy at the center, the lamb's flavor concentrated by the fire rather than scorched out of it. Sloppy execution is lamb cooked grey all the way through, fat left to turn greasy instead of rendering clean, or so much marinade and seasoning that the reason you paid extra is buried. The point of choosing lamb is to taste lamb; anything that obscures that wastes the premium.
This is the higher tier of the souvlaki family. Eaten from the stick it is the plainest expression, the meat and the smoke and nothing else. Folded into pita it becomes the wrapped form, Souvlaki Arni se Pita, which builds directly on this same grilled lamb and deserves its own article rather than being crowded in here. The pork version, Souvlaki Hirino, is the cheaper and more common counterpart and likewise stands on its own. What defines arni is simply the meat: traditional, costlier, and grilled so its own deeper flavor is what comes through.