After reading everybodies response, isn't a "STANDARD" team, what you are familiar with. I mean there common pokemon on teams, people just change it up a bit, because they either like a pokemon or feel it's gonna help them win the match. Also, sometimes they just throw their favorite pokemon in their too
Tauros and Chansey were on almost every "STANDARD" RBY team. So that takes away two slots. Then people needed a starter, either Exeggutor, Jynx, Gengar. They needed a sleeper, and usually one of those one a sleeper. but those were not Standard, except Exeggutor. Like Borat just said, some people use Chansey as a sleeper, but Sing has horrible accuracy. So, that's one more spot taken. THen people chose either Rhydon or Golem, to Explode or not expode and to take physical normal attacks. So that's four pokemon. Then they needed a special attacker, and since Psychic was the most power attack back then, they would use Alakazam, Starmie, or Amnesia Lax. So that's 4 right there, basically these Pokemon were interchanged off and on with different movesets. The last pokemon could have been anything from Lapras, to Snorlax, to Jolteon, to Persain. They all had their positives and negatives, there was no actually "perfect" team. Lapras for Paraysis, Confusion, Special attack with Bolt/Beam or even Growl and Reflecting Physical attacks. Snorlax, as either Fish lax or Lax with Earthquake, or Amnesia lax, good for take on Zam, Starmie, and Exeggutor. Jolteon for High special attack, nothing really stopping it, except Chansey, Rhydon, and Golem. and Persian for a STAB slash always critical hitting.
There was only two reasons I used Gengar was because of Slash, and to absorb those explosions. he could also explode on Zam, and Chansey, but just to absorbs for me, and I liked how he looked. He might not be standard, but he's defintly something that works well on teams.
Butterfree up your day, because I'll bedrilling you all night