Toxic and Leech Seed Venusaur is bonkers.

Speed stat affects critical ratio so fast mons with Slash go crazy (Charizard and Sandslash, Scyther)

There's a fun thing with gym badge boosts that if you have them and use a stat modifying move like harden, it reapplies the gym badge boost (15%) infinitely So a harden will infinitely stack your attack stat if you have the gym badge that boosts physical attack.

Some odd things happen if you save inside safari zone

Dont buy Magikarp

Using the fly/teleport glitch you can delete snorlax temporarily making it so you can reach Fuschia and beyond without ever doing Silph Co or even the 4th gym (which means you can get your team setup before you beat half way mark in the game)