Ah, sorry for the confusion, I was talking about double FD and single GI anyway. I just wanted to replace the DoD purity with GI, because the only thing I got from DoD was Daode as Commander anyway
Thank you for the responses.
Since he works in command you could (ab)use his ability to utilize the full potential of Secluded Constructor with relative impunity.
Wait, does this mean I can sacrifice robots from the command zone and they don't die cause of the passive from Noble? That sounds rather awesome but it would force me into double GI single FD
I already imagined you were thinking about 2FD/GI, but I wanted to cover both options anyway.
As Stranger42 said, what Noble Protector does here is protect Secluded Constructor from such things as Lightning Blast, Firebolt, Yuanshi's Wrath, etc. A 4 health character is easily killed even in command which is always a risk for anyone who wants to use Secluded Constructor. Counters are so prevalent that normally it's best to have a full set of backup Constructors in the deck if your deck relies on them.
Noble Protector changes this because almost all cheap counters to Secluded Constructor rely on dealing damage. This means you can get away with not running spare Constructors (which would often be a dead draw) and you don't have to worry about your constructor getting killed with priority as much (which can mess up your plans).
One thing you should keep in mind is that Noble Protector only protects against non-combat damage caused directly by your opponent. This means he won't protect against your own abilities, but it also means he won't protect against the effect of poison or immolated status effects. In this case the damage is caused by the status effect and not the ability that caused the status effect. So your characters can still die to poison or immolate damage.
Of course you could forgo the Constructor entirely as MerliniX shows. GI is very strong even without it and that way you don't have to sacrifice two command slots for cards that don't provide direct pressure. Since you are fairly new I imagine you're pretty far off from being able to build that deck though (I'm not even close myself).