Dual STAB Mixed Attacker: Grass/Ground - While packing a serious 4x weakness to Ice type attacks, STAB Ground and STAB Grass would prove an excellent combination for attacking a lot of big time threats in the tier, especially if a stat boosting move(s) is available in its movepool (STAB Earthquakes would really hit Gengar and Chansey, STAB Razor Leaf/other grass attacks would really hit Rhydon, Starmie, and Cloyster), while also being healthily walled by common threats (namely Exeggutor and all flying types). A simultaneous QuakeSlide resistance and Electric immunity would provide the Pokemon plenty of defensive utility as well to balance out its awful Ice weakness, making it a pushover to some sets and a real offensive menace to others.
A lot of RBY grasses can't really hit special walls like Chansey, or Psychic types for anything meaningful without using non-STAB normal type attacks, such as swords danced hyper beams or explosion, which let in Gengar for free. This Pokemon would get the physical STAB necessary to deal with special walls while also simultaneously keeping Gengar from coming in to ruin the fun, but also possessing the special STAB to make sure the physically bulkiest mons of the tier, like Cloyster and Rhydon, can be swiftly defeated as well. Overall, this type combination should prove balanced on a Dual STAB Mixed Attacker archetype.
Priority Revenge Killer: Normal/Rock - Normal typing grants STAB to Quick Attack, and Rock could benefit some sort of hypothesized secondary priority move if it needs to hit a weakened Gengar or other Ghosts, while still giving it a very vulnerable defensive typing for a lot of the "slow and bulky" mons of the tier to make quick work of, like Earthquake from Snorlax or Rhydon, Mega Drain from Exeggutor, Surf from Slowbro, Clamp from Cloyster, etc. Rock typing would also allow it a wonderful Hyper Beam swap in as well to hit potentially hit hard with STAB on the recharge and then promptly STAB Quick Attack, allowing two free attacking turns to punish sloppy hyper beam usage. Overall, the type combination should lead to a mon with a decent typing for revenge killing/stopping sweepers in their tracks.
Anti-Lead: Bug/Ice - Bug type clearly offers STAB to deal with all of the common Psychic type leads, while Ice type offers a Blizzard resistance and freeze immunity from the likes of Starmie and Jynx. Although it has no weakness to any of the common attacking types of the tier (neutral to Electric, Psychic, Normal and Water, resistant to Ice and Ground), it gets obliterated by anything packing Rock Slide, Drill Peck, or Fire Blast, while offering no comfortable way to take STAB attacks from a good chunk of the later game hitters, such as Tauros, Zapdos, back Starmie sets, Slowbro, etc. As a result, this mon wouldn't hardwall any OU staples, nor obsolete any of their roles, but would boast its own unique blend of resists and weaknesses, especially in a lead position.
