This season's design features a motto:
Yes, I have done something for House Kaari as they're an original creation by me and these are generic images that CafePress has if you want to design something via their site.
'Bow Before No Mortal Or God' is House Kaari's motto. It shows that they are very determined and don't change their mind because they are afraid. They will work with others if they feel it is the right thing to do, not because they fear repercussions or think it is their duty to work with others.
The symbol of House Kaari is a winged serpent consuming itself (basically an ouroboros with wings). The symbol of House Targaryen is a three headed dragon. So the picture itself shows the intense rivalry between House Kaari and House Targaryen. There didn't seem to be a way to do House Kaari's sigil so I didn't attempt it.
You can read the fic HERE.
You can get this design and others HERE.
If you have suggestions for future designs, please tell me in the comments below.