I have been working on a Empcor (Empoleon & Gliscor)
Empoleon is only weak to Fighting, Electric and Ground, Glis is immune to Elec & Ground and takes fighting hits like a champ. That being said Glis doesn't like Ice and Water in which Empleon is a x4 and x2 resist.
The only type they cannot resist completly is Grass/Fire.
The only problem with grass types here is grass knot, and both take neutral damage from it. Fire is also not a problem, since both of them can take out Infernape and Heatran.(Empoleon blocks heatran, Infernape is stopped by Gliscor)