My diamond team sucks

[TBgamer4life]

hey, i'm playing pokemon diamond at the moment. I'm new to the game and don't know the good pokemon yet (the ubers or must haves), right now it doesn't work out quite well. right now, I have my fourth badge(rock, fighting, water, grass ones) and my team is:
27 monferno: flame wheel, grass knot, mach punch and cut
31 luxray: shock wave, thunder, swagger, bite
28 kadabra: teleport, confusion, psybeam, reflect
28 staravia: fly, aerial ace, quick attack, wing attack
28 pink shellos: blizzard, rain dance, mud bomb and water pulse
25 graveler: magnitude, rock smash, rock smash, strength

I know, my team sucks, i made a lot of mistakes (teaching cut to monferno, rock smash,...) but i don't know good hm slaves, i'd like to switch graveler with something else, he keeps dying all the time.

what should I change? whats a good tank (high defense), sponge (high sp defence), sweepers,...?

i'd like a dragon pokemon, but don't know where to find one, people say get bagon, gyarados or dragonair but I don't know which one is best for in game.
I CANNOT TRADE OVER POKEMON FROM OTHER GAMES UNFORTUNATELY
thanks in advance

-TB-

 

[TBgamer4life]

lol epic trollness, do i need a psyduck then? :P no serious, i need help with my team

 

[1UpedAngel]

Find a Gible at that one Cave underneath the Cycling Road.

 

[jab2033]

If you can't trade, why are you using Kadabra and Graveller? You need to trade for their final forms.

And yes, Gible will be your best choice for a dragon, as it will evolve into the powerhouse that is Garchomp.

Don't worry about HM moves. There is a move deleter in the town of the 6th or 7th Gym. For HM Slaves, Bibarel works nicely.

 

[TBgamer4life]

If you can't trade, why are you using Kadabra and Graveller? You need to trade for their final forms.

And yes, Gible will be your best choice for a dragon, as it will evolve into the powerhouse that is Garchomp.

Don't worry about HM moves. There is a move deleter in the town of the 6th or 7th Gym. For HM Slaves, Bibarel works nicely.

what do you think is a decent substitute for a tank and sp att sweeper? i caught a gible, but he's really slow to train, i think i'll succeed though

 

[Ephemeral Euphoria]

I'd replace the Shellos with a Magikarp you can train up to a Gyarados, replace Graveler with a Gible as well even though that can take a while to fully evolve but it is worth it, and replace Kadabra with something along the lines of a Bronzor as Bronzong is a very good tank to use. Also consider replacing Staravia with either a Zubat to evolve into a Crobat or a Murkrow to evolve into a Honchkrow but Staraptor is pretty decent as well so the last bit isn't as recommended imo.

That, and you should try to evolve your Monferno and Staravia as well.

Hope this helps.