We'll start of with Dark Armed Dragon (DAD) from PTDN, a secret rare, worth a whopping £120!!! Of coures you could get it cheaper from eBay. Onto the card:
Level 7/Dragon/ATK 2800/DEF 1000
Effect: This card cannot be Normal Summoned or Set. This card cannot be Special Summoned except by having exactly 3 DARK monsters in your Graveyard. You can remove from play 1 DARK monster from your Graveyard to destroy 1 card on the field.
Pros: Easy to summon. Massive ATK. Brilliant Effect.
Cons: Terrible Defense. Book of Moon can harm him. You can chain his effect with spell/trap/monster. If you dont OTK, the opponent might destroy him with Spell/Trap. Only 1 way to summon him.
In my Opinion 9/10
Now, Judgment Dragon (JD), just as expensive as DAD. Secret Rare.
Level 8/ATK 3000/ DEF 2600
Effect: This card cannot be Normal Summoned or Set. This card cannot be Special Summoned except by having 4 or more "Lightsworn" monsters with different names in your Graveyard. You can pay 1000 Life Points to destroy all other cards on the field. During each of your End Phases, send the top 4 cards of your Deck to the Graveyard.
Pros: Helps Lightsworn. High ATK+DEF. Easy Summoning Conditions. OTK's are simple. You can have 4+.
Cons: You can chain his effect with spell/trap/monster. If you dont OTK, the opponent might destroy him with Spell/Trap. Only 1 way to summon him.
In my Opinion: 9.5/10
Judgment Dragon won. I think DAD's ability is great, but in the late game, you will probably have more then three DARK's in the graveyard. Judgment Dragon is 4+. and that is easily fulfilled with Lightsworns effects.
Do you agree?