The animated armour is one of the game's most daunting foes. With massive attack damage and one layer of death protection per level, this monster is rightly feared as one of the most powerful in the game. Low-level animated armours have relatively few layers of death protection and can be reasonably handled so long as you act with caution, but high level ones require a massive expenditure of effort to take down and are stronger than many boss monsters. Their only weakness is that their attack damage degrades every time they lose a layer of death protection, but the fact remains that the amount of effort required to weaken this monster is comparable to the amount of effort required to kill other types of enemies outright.
Due to their massive damage, most characters without excessive magic resistance will not be able to survive a single attack from a higher-level animated armour. Combined with their relatively low hit point total, a spellcasting approach is much preferable. Reducing their hit points to zero is just the start, and you must also remove layers of death protection one by one. Because even one point of damage can strip a layer of death protection if the monster is otherwise out of hit points, there are several useful ways to knock out DP.
The easiest way is to use burning damage from fireballs. Igniting the burning damage by attacking a different monster will deal a small amount of damage, but if the animated armour has 1 HP then this will still knock out a layer of death protection. Knockback damage is also an effective approach; this technically qualifies as a separate attack from your main strike, and can allow you to remove two layers of death protection per hit. The Sorcerer has the mana shield special ability that technically counts as a separate attack, and it can also remove a layer of death protection. A Sorcerer with a Bear Mace and Whurrgarbl can potentially remove four layers of death protection per hit by combining each of these techniques. The PISORF glyph is another cost-effective approach to deal a small amount of damage and remove death protection.
Removing death protections by physical attacks can be difficult. Normally Life steal effects are good at attrition battles like these, but due to how Death Protection works you are technically doing only 1 point of damage and effectively do not heal any damage from your attacks. In these cases, it can actually be beneficial to allow the animated armour to heal between attacks so it has more life to drain. Even when weakened, animated armours still deal large amounts of damage and finishing them off by physical means is difficult.
The Assassin is the only class in the game that has a trick up his sleeve to death with animated armours. His swift hand special ignores all forms protections and instantly kills the target, bypassing all layers of death protection in the process. The 9th level animated armour is a terrifying foe that most players will ignore outright and refuse to attack, but a 10th level assassin can make a mockery of it. The Slaying Wand can also be used to remove these monsters from play, but this will deprive you of the full XP amount in most cases.
The animated armour boss, the Indomitable, is one of the few bosses that is actually weaker than the base monster type. His damage is roughly half as much as you would expect from a 10th level animated armour, making him considerably easier to take down than a 9th level animated armour. However, if you should engage him in the Vicious Halls of Steel alternate level, he has a shocking 50 layers of death protection and a corrosive attack.