Sorry,my computer won't let me edit my previous post
Also,is there a way to incorporate this trope somewheres?
"Fantastic Fragility
Everything has a weakness, every lock has a key, every curse a loophole, and the flaw will come into play to bring down the device.
This applies to basically every "immovable object" and "unstoppable force" in fiction, be they objects, characters, science, or magic. The idea is twofold: inside the story, the creator of the device or technique may incorporate a Necessary Drawback that will make it stronger, while the author gives the protagonists (or antagonists) a way to defeat it and maintain suspense and narrative flow by limiting the Deus ex Machina.
When justified in a setting, it's usually explained that magic is not free, and the only way to make an unstoppable whatever is to, ironically, build in a weakness that makes it stoppable. Clever creators may even keep the weakness a secret to use in case the machine (or person) should be turned against them. Others may try to make it an Impossible Task.
It can be a key to an Tailor-Made Prison, a physical weak point, not being able to harm virgins or the like, or a Curse Escape Clause. If the weakness is a Power Source, Soul Jar, or a form of remote control, destroying the "Keystone" destroys the device/weapon/person/army.
See Also Celestial Deadline, Necessary Drawback, and Power at a Price. Compare Achilles Heel, which is this for creatures/characters"
I'm thinking the Voidspawns inability to use armour might count as this. If, ARMOK FORBID, The Voidgod gets killed, it will probably also be this.