This deck is almost same as the basic Elements Unite deck to farm regular Legendary Duelists (LDs). If you are not familiar with it, check the link below. The one thing you must note is bringing Trap Jammer to negate the activation of Mokuba'sNegate Attack. This deck can't be used against Mokuba Lvl 30 since he has Poison of the Old Man.
Keep stalling with Labyrinth Wall while using draw cards. Only set Crystal Seer if you have at least 2 cards left in your deck, and only use Shard of Greed if you have at least 4 cards left, to avoid clogging your field.
All trap cards in this deck are to help deal with ritual weapon. The Emperor's Holiday would be the best out of all of them since he negates the effects of all equip cards. Making this deck useful against Mokuba Lvl 30 also.
Unhappy Girl (6k-8k)
If you don't have Paradox Brothers, use this deck. 100% win is not guaranteed, but works pretty well. If you are not familiar with this type of deck, check the link below to learn the basics. This deck can be used against Mokuba Lvl 30 as well.
Another great event that I won 20 duels with 9K assessment and still could not get a single copy of Frost and Flame Dragon. The amount of shitty rewards like jewels and gold chests are absurd, and Mokuba kept giving me Kidmodo.