Omnath, Locus of the Roil Omnath, Locus of the Roil is a strong midway point between having a lot of elementals in play and a lot of lands
"Ursarctic" Synchro Monsters also have a special Summoning condition where the difference between the Levels of the pseudo-materials is used to perform the Summon, as that is what has to match the Synchro Monster's Level rather than the sum
Number 92: Heart-eartH Dragon, and its Number C form, Heart-eartH Chaos Dragon, both cannot be destroyed by battle
If you want to win one of these events, I suggest that you use PTCG Live, an online simulator that can help you to practice with your friends
While there are multiple versions of this card, the edition given to the top 16 finishers in the tournament commands the highest observable value due to the higher-tier finisher versions being too rare for TCGplayer to accurately assess