Pokemon lake.com & Pokemon crater
You can't fuse Pokemon.
There are many Pokemon fan websites and other websites that offer a Pokemon Sapphire walkthrough. Some of the websites that offer a free walkthrough are Bulbapedia and Psypokes.
If by last Pokemon you mean the last one in the pokedex then that'd be Arceus, #493
pokemon.com
Go to pokemon-poke-mon.webs.com
you could try Pokemon moon, Pokemon indigo, Pokemon lake, Pokemon volcano
yes arcaeus is the last Pokemon in the pokedex
Well, there's pokemonvolcano, pokemonindigo,...
i think the last pokemon is deoxys or jirachi if not it is raquaza. (groudun, Kyogre)
yes
slowpoke