Raichu
Thunderbolt
Surf
Submission
Thunder Wave
I wanted a good lead to slow down the target with Thunder Wave without giving up Alakazam, and Riachu was the next best option to me because Rhydon can't wall it unlike other electric types.
Venusaur
Razor Leaf
Sleep Powder
Swords Dance
Hyper Beam
I felt like Swords Dance and Hyper Beam could be a scary combo, so I looked at all the Swords Dancers, and the ones I found to be the most consistent were Venusaur and Victreebel. I picked Venusaur because the extra physical bulk and speed seemed more valuable than Victreebel's higher attack.
Articuno
Blizzard
Double Edge
Hyper Beam
Agility
While not a true blue OU pokemon, Articuno is not a pokemon you want to mess with. It hits HARD with Blizzard, most checks still take Ok damage from it. Agility can help Articuno offset it's average speed, then the normal moves help it do more damage while saving Blizzard PP.
Alakazam
Psychic
Reflect
Thunder Wave
Recover
Alakazam is a solid pokemon, with Thunder Wave support and good damage with Psychic, and it's not that easy to get rid of either thanks to Reflect having physical damage and Recover healing it by 50%.
Rhydon
Rock Slide
Earthquake
Seismic Toss
Counter
Rhydon is the best answer to Zapdos who is a scary pokemon, so I feel like I need it. Rock Slide and Earthquake are hard to resist when on the same pokemon. Seismic Toss helps deal damage to bulkier pokemon and Counter can punish Hyper Beams.
Tauros
Body Slam
Blizzard
Earthquake
Hyper Beam
Tauros is the best pokemon in gen 1 OU, so of course it is joining the team. Body Slam is a great move with Para chance and solid damage, Blizzard and Earthquake are very good coverage moves, and Hyper Beam does big damage.