This is a much more useful effect to find a land for a color you are missing
You can play the land, but you still have that one-land-a-turn limit
However, that was just reprinting six cards, and there are hundreds of new cards in the 40k commander decks - not to mention that the Astartes, Necron and Tyranid creature types are part of Games Workshop's intellectual property, so presumably can't be reused without their license.
Thats all well and good
Pillar Analysis: High Power (Dual Land), Scarcity (Beta, Reserved List), Format Essential (Control Decks)
Balance First Printed: 1993-AUG Banned: On its face, Balance looks like a very effective catch-up strategy thats mechanically very white, but in practice it leads to slow, long games with a low density of meaningful decisions or memorable events