who do you recommend for this GSC themed team?

[PDL]

alright I've been designing another team, this time, it's a GSC themed one, so only GSC pokemon count

so far, the following pokemon are definately on it...

Tyranitar (what's a Tyraniboah?)
Blissey
Lanturn
Bellossom

however, I have been thinking about adding 2 of the following:

Crobat
Xatu
Girafarig
Donphan
Forretress
Steelix

which 2 would be best for the team?

 

[Primo]

You should go with what KaO said and forget about Steelix (high def, piss poor everything else) and get a Flying type so you can use Tyranitar's EQ in double battles.

Crobat has ALOT of weaknesses, but with a good moveset and nature he can be pretty useful.
Crobat @ Leftovers
Calm Nature (+sp Def, - ATK, good for his Electric, Psychic and Ice weakneses)
Haze
Sludge Bomb (acc. as hell and with STAB its amazing)
Aerial Ace (takes a hit from Calm Nature, but always hits and gets STAB)
Substitute

Xatu has some good Sp ATk so maybe one with
Calm Nature
Psychic
Featherdance
Haze
Substitute

So pick one of those, and I don't know the other, but I'm sure chaos or 0mastar will give you a suggestion when they come in here to yell at me :/

edit:
Go catch a Jolly Heracross, since you could use some Bug/Fighting type moves.
@Salac Berry, but those DO take a while to grow.
Megahorn
Rock Slide
Swords Dance
Brick Break
Make it a Physical Attacker.

 

[SPN]

This is Rate My Team, not Make Me a Team. But if I had to pick, I'd go with Crobat and Girafarig since your first four don't have any real sweeping capabilities.

 

[Double-Edge]

if you want a good strong GSC based team, go with

Heracross (physical Sweeper)
Jumpluff (Sporer)
Octillary (Special Sweeper)
Blissey (Sponge/Special Wall/Heal Beller)
Scizor (Baton Passer)
Lanturn (cover all weakness)

You can go with Tyranitar

im not posting movesets, just giving a choice of the best GSC pokemon

 

[~-=Mewtwo=-~]

I'd think of Skarmory... But being In-game not completely... do NOT and I repeat do NOT make Tyraniboah ingame... first you MUST have 31 IV's and 252 EV's in HP... then you give it a crappy moveset... (Crunch/Ice Beam, Thunderbolt/Fire Blast/Flamethrower, Substitute, Focus Punch) To take down Celebi, Salamence, Skarmory, All Normal Types... etc... Plus it just sucks ingame Boah is a downfall here... Just breed DD and put EQ, Rock Slide, and AA/HP Flying/Taunt on it... And a Jolly Nature... with 212 spd EVs to make sure you get to at least 198 spd at level 100 even if the IV is 0... 252 Atk.. and 44 in HP... If you don't care about the EV's just slap an Adamant (Not a Jolly Nature here) Nature and the Moves on