Dead shielded Emile
In the final level, The Pillar of Autumn, near the end of the level at the Onager Mass Driver, one can find Emile's dead body lying against a railing, among some dead Zealot Elites. Both Emile and the Zealots have shielding, and cannot be "killed." You can shoot them, causing their shields to flare as if they were still alive, but no matter how much damage you cause to them, they will not "die", meaning ragdoll physics will never take effect. If you manage to take their shields down, they do not recharge. Since they are still technically "living," you cannot walk on top of them, as living NPCs act like solid objects. They do not respond or move at all.