Want to play a pokemon randomizer on an actual ds without much effort at all or modding or anything?
First, look for a 208 in 1 cartridge on amazon. Right now mist of them say unavailable, but the first pic is what mine looks like.
Second, simply put it in and start the game. It will read as a spongebob game or something random.
Third, scroll down to the pokemon game you want to play and press Y. This brings up the menu in the 3rd pic. Then press X to bring up the cheats menu
Fourth, select "encounter codes" and select "Encounter random wild pokemon". Now just press B until you go back to the game selection list

Thats it. Thats all there is. Works for all pokemon games for the ds (and this cart has all of them). Theres also some more neat cheats on here like picking your own starter, group leveling like newer games, ect so check em out