Which gen 2 pokemons were supposed to appear in gen 1? Also,

>>33035234
That is a question that cannot be answered by anyone not in Game Freak at the time.

All we know is in total they had 191 of them (190 were in, they cut 40, and then Mew took the first of the 40 emptied spots just before release).

For all we know, some of the 40 removed were later entirely scrapped.

The index order in Gen 2 doesn't tell us anything either because Gen 1 was entered in order of creation but the Gen 2 ones were mostly put in starting from 190 in dex order and then looped back around after hitting 251 to fill the empty slots.

So the Gen 2 Pokémon you get by sending the glitched ones over aren't likely to be the ones who filled those slots originally even if all 40 did return.

>>33035508
As for why they were cut, it was because they were saving them for Gen 2, which was originally intended to be the end of the series.

>>33035508

I recall a Smogon thread where someone asked Morimoto about Ho-oH at an event regarding this.

Morimoto says that Ho-oH wasn't a planned gen 1 mon despite the anime appearance.

So we know that.

>>33035508
There were 190. Mew was one of the cut 40, but was readded at the end after the debugging stuff was cut. The 39 Pokémon that didn't make it in can't be confirmed. Even the Pokémon that took those missing index numbers in Gen II aren't indicative of what they were originally supposed to be since you can see why they're ordered the way they are.

>>33035514
Gen II wasn't intended to be the end of the series. I've heard nothing like that.

Anyway, the ROM size to Red and Green are 512 KB, and they are a mess to look at in hex. Someone could rip everything, remove all unused material, redo all the ASM programming to make it more stable and less prone to glitches, and still end up with more space remaining than what Game Freak had.

>>33035234
We know that Kakuna's original evo was a scrapped version of Ledian, and that Poliwhirl was originally gonna evolve into a fatter Poliwhirl wearing a crown, suggesting that it got reworked into Politoed (king's rock)

>>33035234
I have no sources, but I recall reading that Lugia and Tyranitar were planned for gen 1

Why isn't GEN 2 counted as part of GEN 1?
Jotho and Kanto are the same thing

They were cut because game freak is incompetent