Yes, a Zapdos could defeat a Rhyhorn if the Zapdos did not use any electric type moves. I'd use Flying type moves.
Then you have some options: 1) Don't care about it and not having him. 2) Use a Gameshark to get another Zapdos 3) Turn off your game and not defeat him.
If you defeated Zapdos, you can never get him again, unless if you trade from Pokemon LeafGreen or FireRed. If you did defeat him, you should have saved the game before pressing the button, A, on it. That way, if you defeat him, you can just turn off the game and turn it back on and you will find Zapdos still there! ed by: QWERTY
Outside the Power Plant after you defeat Gary/Blue.
Step 1: Break your game YOU LOSER Step 2: Burn any Pokemon related items YOU LOSER Step 3: Get an PS3, now ur an up to date LOSER Step 4: DIE
you finish the game with heart gold then you go to kanto and you defeat gyms and on the way you'll get zapdos moltres mew mewtwo an so on
i'd try to use one hit kill moves or just legendarys
Rhyhorn evolves at level 42
You defeat Giovanni (which is also the Team Rocket Boss). He is in Viridian City, and his Pokemons are Rhyhorn, Dugtrio, Nidoqueen, Nidoking, and Rhydon.
You can find Zapdos in Power Plant only once so if you let Zapdos fly away or if you defeat it you can never find it again in LeafGreen.
What I did is keep on killing it until it asks to join. (If you want to recruit it make sure you hit it last when it faints, not your partner. You can tell your partner to get away while you defeat Zapdos.)
Rhyhorn evolves into a Rhydon at level 42.
Just come back, it will be there again. All legendaries reappear should you defeat them and not recruit them.