diff --git a/src/mudlib/commands/snapneck.py b/src/mudlib/commands/snapneck.py
new file mode 100644
index 0000000..cc39714
--- /dev/null
+++ b/src/mudlib/commands/snapneck.py
@@ -0,0 +1,98 @@
+"""Snap neck finisher command."""
+
+from mudlib.combat.engine import end_encounter, get_encounter
+from mudlib.commands import CommandDefinition, register
+from mudlib.player import Player, players
+
+
+async def cmd_snap_neck(player: Player, args: str) -> None:
+    """Snap the neck of an unconscious target.
+
+    Args:
+        player: The player executing the command
+        args: Target name
+    """
+    # Get encounter
+    encounter = get_encounter(player)
+    if encounter is None:
+        await player.send("You're not in combat.\r\n")
+        return
+
+    # Parse target
+    target_name = args.strip()
+    if not target_name:
+        await player.send("Snap whose neck?\r\n")
+        return
+
+    # Find target
+    target = players.get(target_name)
+    if target is None and player.location is not None:
+        from mudlib.mobs import get_nearby_mob
+        from mudlib.zone import Zone
+
+        if isinstance(player.location, Zone):
+            target = get_nearby_mob(target_name, player.x, player.y, player.location)
+
+    if target is None:
+        await player.send(f"You don't see {target_name} here.\r\n")
+        return
+
+    # Verify target is in the encounter
+    if encounter.attacker is not player and encounter.defender is not player:
+        await player.send("You're not in combat with that target.\r\n")
+        return
+
+    if encounter.attacker is not target and encounter.defender is not target:
+        await player.send("You're not in combat with that target.\r\n")
+        return
+
+    # Check if target is unconscious
+    if target.posture != "unconscious":
+        await player.send(f"{target.name} is not unconscious.\r\n")
+        return
+
+    # Execute the finisher
+    target.pl = -100.0  # Instant death
+
+    # Send dramatic messages
+    await player.send(f"You snap {target.name}'s neck!\r\n")
+    await target.send(f"{player.name} snaps your neck!\r\n")
+
+    # Send GMCP vitals update (only for Players)
+    from mudlib.entity import Mob
+    from mudlib.gmcp import send_char_vitals
+
+    if not isinstance(target, Mob):
+        send_char_vitals(target)
+
+    # Handle mob despawn
+    if isinstance(target, Mob):
+        from mudlib.mobs import despawn_mob
+
+        despawn_mob(target)
+
+    # Pop combat mode from both entities if they're Players
+    from mudlib.gmcp import send_char_status
+
+    if isinstance(player, Player) and player.mode == "combat":
+        player.mode_stack.pop()
+        send_char_status(player)
+
+    if isinstance(target, Player) and target.mode == "combat":
+        target.mode_stack.pop()
+        send_char_status(target)
+
+    # End the encounter
+    end_encounter(encounter)
+
+
+# Register command
+register(
+    CommandDefinition(
+        name="snapneck",
+        handler=cmd_snap_neck,
+        aliases=["sn"],
+        mode="*",
+        help="Snap the neck of an unconscious opponent (instant kill)",
+    )
+)