If you mean using other peoples' thunderus and tornadus then yes but if you mean not having either one at all, then nope.
no you cannot when tornadus and thunderus landorus gets mad the you have a chance to catch it
Specifically with only White, you can catch: Zekrom, Thundurus, Cobalion, Terrakion, Virizion, Kyurem without trading or events. By trading with Black, Reshiram and Tornadus become available. If Thundurus and Tornadus are in the party, Landorus is available. Keldeo, Victini, Meloetta, and Genesect are event exclusive, although they can only be found by hacking currently except for Victini.
get one of your Pokemon to learn false swip get it down to 1 hp and either paralyz it or put it to sleep then use the best pokeball you have
These are the Pokemon I know you can get without Action ReplayReshiram (When finish game, it will appear)Cobalion (In Mistralton Cave)Terrakion (In Victory Road)Virizion (In Pinwheel Forest)Rotom (Trade for Ditto from scientist on Route 15)Kyurem (In Giant Chasm)Volcarona (Not legend but in Relic Castle)Landorus (If you get Tornadus and Thundurus, go to abundant shrine)Tornadus (When finish game, wondering around Unova)Genesect (Event)Keldeo (Event)Meloetta (Event)So if you want legends, look at this.By Ojas Bhandari
Without specially breeding the following pokemon can: Snorlax, Sudowoodo, Nosepass, Bastiodon, Bronzong, Bonsly, Tangrowth, Probobass, Landorus
To get Thunderus in Pokemon White, Beat N in the Pokemon League, and go to Route 7. There, and old lady will tell you a legend about Thunderus, and upon leaving her house, you will see him. He will then flee, but look on any of the electric signs and they will say something about a mysterious thunder storm somewhere. Go to that place, and wander through the grass and you will fight him. He'll flee, and find him again, and again, until you catch him. (There is no easier way without hacking.)
You'll need to defeat the Elite Four again and they'll roam by their selves without manually going back to Route 7.
(If without cheats, here) Kyurem, Dragon/ice type. Found in Giant Chasm. exit through the back, find an empty pond. click the a button. It will become a complete whiteout, allowing you to go where the trees were. Reshiram, Dragon/fire, part of the story. N's castle. Comes in at the top of the castle. Tornadus, flying, a wandering legendary. Route 7. Walk into a house, talk to the people, and walk out. Landorus, flying/ground, Abundance Shrine. Requires Tornadus and Thundurus, unable to recieve in pokemon black. Virizion, fighting/grass pinwheel forest, after elite 4. Terrakion, rock/fighting. Victory Road, after elite 4. Cobalion, Steel/fighting. (indefinate) Challenger's cave, after elite 4.
either a. turn of the game, without saving and find him once more. b. re-beat the elite four to make him come around again. both options will make Tornadus reappear
Well if you want to catch a tornadus get a golbat that knows the move mean look then use it on the tornadus and it cant escape intill u beat it or run or capture it then make it have low hp but have like over 40 ultra balls and start to throw them and hopefully u catch it
Impossible without cheating.
The only way to get manaphy without Pokemon ranger is to get it from a Nintendo event.