(Choosing Clefable instead of Elgyem for alien invasion is an interesting choice. I mean if actual alien overlords came and took over the earth, used human kind as a food source AND they looked like Clefable, now that would be terrifying

).
This team will be a dream team based on how much I loved these pokemon, not on how useful each of them are or the entire team is as a battle team.
(By not particular order).
1. Gazer the Watchog. My heroine from my Black2 Blind run. You would never expect a Patrat to be your MVP, but Gazer really was, using one of the most versatile move pools + Return to crush so many opponents by herself, and even slay mighty dragons.
2. Talisman the Starmie. My MVP from my Anti-Ash Yellow run. You practically single-handedly (well, bad metaphor in your case) won me the entire game defeating the majority of threats this game had to offer, including most of the E4 team. Psychic is so OP in gen I.
3. Quake the Hariyama. My one and only MVP of my Sun Blind run (especially after my starter died). Such a powerful pokemon that survived so many battles since the very beginning against all odds, and even miraculously made it alive after the E4 when so many others fell.
4. Scythe the Incineroar. And yet another pokemon from my Blinded by the Sun run, man I really enjoyed this run. Scythe was such a hero, and almost made it all the way to the end until he died saving me from Lusamine in one of the greatest massacres I ever had which I barely recovered from. I learned to love him so much in fact, that it almost made the Litten run my new favorite line for a while (sadly, nostalgia is a powerful force, and so far no pokemon managed to replace the Charmander line. I'm still waiting for the one who does, and in all likeliness it will be a Fire starter).
5. Wazir the Inteleon. Not putting Wazir here will be dishonorable. I don't think Wazir is in the top 6 favorite pokemon I ever had, however his feat is so remarkable I had to put him on this team. After I lost my blind Shield run by losing my entire team to Leon the Unbeatable Champion, on my second Sword attempt I was extremely nervous when I came to fight him again. The battle was extremely tense, I lost 5 of my pokemon to him and was sure I was doomed once more, but then Wazir managed to overcome his last two pokemon including his notorious Charizard who killed most of my team last time, and win me the game. It was a truly glorious moment.
6. Orkhon the Mudsdale. I love Mudsdales, yet for some reason I lost two of them before I finally managed to take Orkhon all the way to the end. Though modest, this Stamina fueled powerhouse crushed everything in its path, such a glorious war horse!
So many other great heroes didn't make it to this list, but are at least remembered in my hall of fame.
Some type redundancies but overall I'd say this is a pretty solid team I'd be proud to use in a pokemon battle with so much glory attached to each of these pokemon.
Well that was fun!
Make a team based on the 6 wonders of the "7 wonders of the ancient world" that sadly no longer exist (Hanging Gardens of Babylon, Temple of Artemis, Statue of Zeus, Colossus of Rhodes, Lighthouse of Alexandria and the Mausoleum at Halicarnassus).