under the 3.5 edition codex, night lords were easily the worst legion in terms of rules... they got extra raptors which were simply over-priced assault marines for the loss of 2 heavy support slots.
rules-wise now, each legion is roughly equal in power... you can build pretty much anything quite easily.
in terms of backstory, i don't think there is a 'worst' legion really! all the traitor legions have cool little plot twists and flaws that make them so tragic and allowed them to become easy prey for the chaos gods!
cheers!
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"Who are you to question my methods?! A 'Puritan' is simply a coward who hides behind a veil of pretended faith and denounces his loyal brother as a traitor out of simple jealousy!"
- Inquisitor Odion   |