This deck is made to farm LDs using Jam Breeding Machine, which you can give to your opponent using either Tea's "Surprise Present" skill, or Gift Exchange. It's effective for most LDs, as long as they can't destroy the spell.
Send a Jam Breeding Machine to your opponent by using Tea's "Surprise Present" skill, or Gift Exchange. The AI will always use it, preventing them from being able to summon other monsters in attack position. They can still summon 1 monster on the turn they activate the card though. Alternatively, you can bring more Gift Exchange and only 1 Jam Breeding Machine with more card draws if you want to use other characters without exclusive skills.
Destroying the monsters
Use the low level cards in your deck to destroy, or return your opponent's monsters. Destroying multiple monsters/Jams will give bonus points, but make sure that you don't attack the attack position Jams to deal any battle damage.
The Jams will only attack on the turn they are summoned, and only if you have no monsters on your field.
Preparation for the final attack
To increase Vassal's damage to more than 10,000, use Blue-Eyes Ultimate Dragon, and another monster with at least 400 attack. When you have 1 card left in your deck, destroy 1 of your opponent's monster, so that on your last turn, there will be a face-up attack position Jam.
Vassal and Union
You can summon Vassal once your opponent has activated the Jam Machine, and they don't have monster(s) with attack higher than your Vassal. This is so that even if you get Temple of the Kings, or Serket as the last card, you can still tribute summon on the last turn. If you destroyed a monster when you have 1 card left in your deck, there will be a attack position Jam on your last turn. Use double Union Attack on to your Vassal, and attack into the Jam.
Xing Zhen Hu is a fun card for this deck. Your opponent's thinking "surely there's a reason they gave me this, I better not use it"? Well, block their other Spells/Traps so they MUST activate it to make room! Of course, they could just never set 2, but that's pretty restrictive on its own.