I never got this piece before.
http://cache.lego.com/media/bricks/5/2/4610708.jpg
and a lot of the 2006-2010 Bionicle armors…
Edit: Oh ya, I also forgot this too
http://cache.lego.com/media/bricks/5/2/6076500.jpg
http://cache.lego.com/media/bricks/5/2/6076487.jpg
I wouldn’t count these since they appear more than 2 sets, but they can only be obtain outside of the U.S as of the time.
If only LEGO decided to reproduce that piece again…
Ahhhhhhhhh…
I wanted some more golden bionicle armor, doesn’t matter what kind, I just want a lot of it 
Core hunter’s mask… ;n;
what the heck is that?
anyway I wish I got any '01 masks and possibly lot’sa purple and yellow
It’s the armory on drilldozer.
Any of the differently colored masks from between 2001-2003. That, and a black and silver Avsa. That would go really well with my upcoming self-MOC.
anything in teal
;-;
This piece in a first post is so cool. I would like to see it somewhere in Bionicle with sweet add-ons.
I want that piece so bad now, dang that would be nice to have.
Slizer feet.
gold ignika, gold vahi, sparkly avohkii, and Lhikan’s Hau.
Those brown meg pieces from Humugnosaur (the Ben 10 set).
Also, a black Kaukau.
Well, I have very few G1 sets left (because I sold most of them, back before I knew G2 was coming. 
And I actually had 3 of those Drilldozer chest pieces…but I sold him too.
So in short, I want every G1 piece ever. 
Oh yeah, and might I mention this?
I don’t actually find the drilldozer pieces that useful…
That mask would be awesome to have.
Me wants Metal-Blue Hau!
@tak210 @Garnira The G2 Trans-Blue Gali mask hearkens back to '01 perfectly.
It does indeed!
A lot of CCBS pieces in Dark Red mostly
As for more recent things… the Skull Grinder mask in black, the Skull Spider mask in Dark Red, etc…