This deck has won 5 times out of 5 for me against level 30 Bakura with over 7k assessment each time. In reality, it'll probably win around 70-80% of the time.
Important strategies:
Summon Endymion as soon as possible. Use his effect to destroy any spells/traps including Ectoplasmer. I only have 2 but if you have 3 Endymion, use only 2 D Magician instead.
Use healing spells until you can summon D Magician. I prefer solemn wishes as it will regain more overall life points, but I only have one, so S Berry is there just incase.
Next summon D Magician. Use Blue D Summoner to draw them and thin your deck. Also, if Bakura uses Card Exchange, he will take a D Magician or BD Summoner rather than your Vassal.
Whenever Bakura has 2 monsters in the graveyard, banish them with Gravedigger Ghoul.
IMPORTANT: Save either Dark Magic Attack or Champion's Vigilance for your final turn to prevent Bakura countering your Vassal's attack.
It's important not to let him summon Dark Necrofear.
Also, it's better to sacrifice one of your union attacks with Endymion to destroy an Ectoplasmer, rather than lose the duel, as even with one Union Attack left at the end you will still get over 5k damage, and around 5-6k assessment.
Somebody give that man a medal!
Finally a deck that works for me. Can't state a winrate yet, since i wasted my dices trying various lvl 30/40 farm decks (currently it's 100% 1/1). Used the exact build in the second pic of the thread, got 7300 DA with my glossy/prismatic bonuses.
Anyways, thx a lot bud! :)
If your running this deck with only one union attack and a spell reclamation, remove one Blue Dragon Summoner and add in one Crystal Seer. This prevents your Spell Reclamation from being at the bottom of your deck.