How can a summon be modded using NI?

Found an interesting file in EEKeeper that harbours a code for a miscellaneous item that's a "Black Panther" totem that incidentally no longer works in such a manner. I'd like to change this.

In my recreation of an Evil Drizzt the ability to summon a Panther specifically would be quite a treat but how can this item be modded for the desired affect?