Ah glitches. I took my Scramble of Blue version to show off a fair number of the simpler, less game breaking ones.
For instance, Rage is bugged to shit in RBY. Unlike in future versions of the games, when you pick rage you're locked into it for the rest of the match. This is annoying but not horrific on its own and was likely intended. What clearly WASN'T intended was that if Rage ever missed (whether naturally like all moves in RBY or due to evasion raising/accuracy lowering moves used by the opponent) its accuracy rolls over from the usual 99.6% to 0.4%, essentially rendering the Pokemon using rage completely useless and unable to switch from battle. I used this against my rival's Charmeleon/Charizard twice in my Scramble for the lulz.
Another cool one is that the effects of Leech Seed and Toxic stack in a weird way in RBY. Toxic acts like normal, but Leech Seed gains the intensity increasing characteristic of Toxic if they're used on the same Pokemon. This means that you essentially have TWO toxic statuses on your opponent and
one of them is healing you for all the damage it does. Combined they can take down a Pokemon in 4 turns, and if the opponent heals it can do enough damage to KO them from full health in only 8 turns as opposed to 15 for Toxic. Oh, and one more little awesome bit, in generation I Leech Seed heals you for the amount of damage it WOULD do, even if the opponent doesn't have that much HP left. So if your opponent has a little sliver of health left after several turns of this, you'll STILL be healed for the full amount.
Also there's a huge range of glitch Pokemon in Generation I, just look
here for all you could ever want to know about them.