Though, Garchomp is the better one
It is a really powerful psuedo-legendaries. It have 3 weakness and a 4x from Ice-type. But if have 3 resistance and immune to electric. A total huge Attack and Hp (Next speed) can be seen. Actually, Garchomp learn Fire Fang from the early, and it can be used to attack against Ice one.
Noveirn is another choice, with 5 resistance, 3 weakness(Ice 4x again, that's why I don't like Ice type very much) and immune to ground. Even it is not a psuedo-legendary. If have a bunch of 123 speed. Learning some grass type move can be an advantage to this guy.