It does not need to be used on an object, if used on a wall it will be formed from part of the wall in the shape of a rough humanoid, think classical golem.
Humanoid Figures bursting out of Walls? That sounds like...
It would very obviously not be human and it would be very hard to trick anyone into thinking otherwise.
So no Pillar Men.Yet
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And we cant use them as Double for Eri, still usefull as Distractions. The Mana cost though...
They are as tough as the material they are made from, and collapse after taking too much structural damage.
That is usefull. I'm curious if we could use a collapsed Servant as a base for a new one.
So, I think we need All Mights help with this. Gather Info and Evidence to convince him and other Heroes to help and then either protect Eri until she is saved or get her out ourself.
I think I will make two Plans, one with her waiting and one with us getting her out. Then People can vote for what they want.
[X] Plan Damsel in Distress
-[] Purchase Sanctuary, Visions and Divine Resilience.
-[] Gather more Info about what's going on in the Base, use any Cameras you find to search for a computer system or something else that could be used as Evidence to convince All Might and other Heroes to help.
-[] Inform Izuku that you will need your Mana soon to help save a Life, and that he may take a rest from his training.
-[] Inform All Might about Eri's Situation, and everything else you have learned, and ask him for Help.
--[] If there is nothing to use as Evidence and you dont think you can convince him, wait till All Might is somewhere close to the Base and then use Wrathful Smite to punch a
Hole from the Surface to the Underground Base, attrachting Attention and getting him into Range of your Visions.
-[] If All Might agrees, let him plan how to save Eri, he is a Hero and has Experience with this.
-[] If All Might agrees, or you dont think you can get his help, get Eri to sanctify her Room and the Area around it befor the Attack starts and use Divine Resilience on her, if necessary do that a Day befor the Attack to regain Mana. Then tell her to use Shield of Faith and wait till All Might saves her.
--[] If there are any unforeseen Problems use Visions to warn Eri or All Might, if it isn't to distracting.
The other Plan
[] Plan Za Warudo
-[] Purchase Stutter and Possession.
-[] Gather more Info about what's going on in the Base, use any Cameras you find to search for a computer system or something else that could be used as Evidence to
convince All Might and other Heroes to help.
-[] Inform Izuku that you will need your Mana soon to help save a Life, and that he may take a rest from his training.
-[] Inform All Might about Eri's Situation, and everything else you have learned, and ask him for Help.
-[] If All Might agrees, let him plan how to save Eri, he is a Hero and has Experience with this.
-[] If All Might agrees, or you dont think you can get his help, use Possession on Eri and then use Stutter and your Omniscience to get her out of the Underground Base.
-[] Get Eri to All Might, another Hero or anywhere else she would be save.
So, that would be my first and second draft for a Plan.
Thanks to
@veekie for the Camera bit and
@Trondason for the parts of the Vote I copied.
I vote for Plan Damsel in Distress because I think Eri will be saver with Divine Resilience, Shield of Faith and being inside of a sanctified Room.
The Shield is mainly so that nobody can just drag Eri out, how tough the Shield is shoudn't matter if no one can attack it because of Sanctuary.
Plan Za Warudo has the Possession Part because it should be easier to lead her out like this with our Omniscience than using Visions everytime, not to mention the Mana cost.
It also lacks the Wrathful Smite part because of Mana costs.
I'm a bit unsure about how the Rescue would go and how the Mana use would work out, but I think this should cover most Things.
Or maybe I'm just tired and overlooked something.
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It's pretty late here.