Global Trade Station

I'm thinking about what last pokemon I should take in my team. My variants are: Tyranitar, Gengar, Gliscor, Electrivire
I already have Magmortar, Tangrowth, Metagross, Porygon-Z, Kingdra/Feraligatr(thinking who are better too)

Can someone give any good advices?

who do uhave in ur team atm so then people can judge who fits in well