No, the only way to get a rhyperior is to trade a rhydon holding a protector. Rhydon can be found on Diamond on routes 227 & 228, as well as stark mountain.
You can get a Cyndaquil without trading only by transfering it from a GBA Pokemon Game onto your Pokemon Diamond Version.
In Diamond & Pearl? Impossible without migrating, trading, or Action Replaying.
no you can't you have to either trade or gameshark cheats :P
There is no other way.
not without trading someone elses Pokemon that's holding it
You can if you use action replay :P If you don't use one, then it is impossible to complete without trading as there are only certain Pokemon that can be caught in diamond and vice versa with diamond.
The Pokemon that can be caught without special events, trading, or cheating in Pokemon diamond are: Uxie Mesprit Azelf Dialga Giratina Heatran
The only other way to catch it is to cheat.
No it is not possible. You have to hack or trade.
impossible. u cannot get dialga without trading from a diamond game but the rest u can do.
Trading from Emerald is your most probable option.
u can't