Also, I like to build my characters around my powers. Can I have that Obito Uchiha power that makes him intangible while using his Kamui? SO basically he teleports his body to another dimension and nothing in this world can affect him. So my dimension would be the Shadow Plane. His sheer willpower keeps the creatures on that plane from taking his soul and although he can't see them he can sense them and feel their gaze pierce through him from every angle. His emotionless attitude keeps him hidden from the bigger part of the resident devourers of that realm but there are a few who have marked him and keep on following him everywhere, waiting for an opportunity when he ultimately slips. The longer he stays there the harder it is to keep them away.
He can also open the portal and drag someone through to that dimension and leave them there. Besides the creatures that are there, the plane itself is gradually transforming him. The more time he spends there the more his soul corrupts giving him additional powers from that plane but the time he can spend there with his will shield on gets dramatically reduced as, like I mentioned above, his soul loses it's initial form and so does the will power. He can recover but veeeeeery slowly.
When he comes out of the plane he leaks a shadow essence for some time, a mark that the plane has left on him. He can open small portals with his finger effectively writing with shadows and doing other creative things.
I think you might want to not go with that as a power. Not just because the thought of anyone having Obito's Kamui powers to be intangible is the kind of thing that frankly makes my eye twitch in disturbance, but because I specifically stated that "Time/Space powers are
forbidden." Kamui's abilities, especially as you mentioned, are ultimately Spacial power to a combative level, and while I tolerate "Space" more than I do "Time" (Which, for the record, unless you have some original method of using Time that doesn't involve direct manipulation of its flow, I will never allow,
EVER.) the powers of Obito is something I can't abide by.
...At least in terms of using it to become intangible to the physical realm around you. I understand the weaknesses of Kamui (I did see the fight after all) but I feel it is still too circumstantial to put into proper effect in an RP.
Now, being able to enter a shadow realm, by itself, is a different story. Mostly because I know the PERFECT place to use as the Shadow realm that he enter. There are also another effect you might want to consider using in that respect, perhaps to replace the intangible part, more specifically, maybe opening a portal and letting a Shadow beast or two run loose in the physical realm. I'll have to talk with my partners more about it though.
In other words, Take out the "Intangible/Kamui" effects, and just let this shadow realm and the ability to open a portal into it be your power, and make the CS. ^_^