Sickening Shoal does a great job preventing threats like Ocelot Pride from running away with the game
It plays off of hero synergies, whether you've got Captain America being buffed as they enter, or Nick Fury reducing their cost, and is remarkably easy to play with

Stage 1 Win 6 Duel World Duels Use Skills 3 times in Duel World Duels Stage 2 Inflict 2600 or more points of battle damage in duels Use spell/trap cards five times in duels Perform 3 Xyz Summons in duels Stage 3 Win 8 Duels Inflict 5000 or more points of battle damage in one duel Destroy 3 monsters in one duel Achieve 3 No Damage wins in Duels Stage 4 Win 8 Duels Reduce your opponents LP to 0 by inflicting battle damage with Utopia Perform 5 Xyz Summons in duels Stage 5 Win 1 Duel against Bronk Stone while playing as Yuma and Astral Inflict 25000 or more points of battle damage in duels Inflict 5000 or more points of effect damage in duels Summon 20 monster in duel world Stage 6 Win 9 duels Win a duel world duels with a duel assessment of at least 4000 Achieve 2 No Damage wins in duel world Use Rank 4 or higher Monster cards two times in one Duel World duel Stage 7 Win 9 Duel World duels Achieve 1 Comeback Victory in duels against Yuma and Astral Achieve 2 wins without using any spell/trap cards in duel world Win 3 duels within 5 turns in duel world Stage 8 Win 5 Duels using Bronk Stone Inflict 38000 or more points of battle damage in duels Summon Tin Archduke two times while playing as Bronk Stone Perform 4 special summons in one duel Stage 9 Win 10 duels Achieve 4 Comeback Victories Achieve 1 win using only Machine-type monster cards using Bronk Stone Summon Spellcaster-type monsters 4 times using Yuma and Astral How to unlock Shark Kastle Shark Attack: Numbers Appear

Its attack, Onyx, is unlike anything weve really seen before and lets you discard all Energy attached to Umbreon ex to straight up take an opponents Prize card
Its an interesting decision, and while its definitely one thats split the player base a little, it does make for an interesting time
Even as just a young girl, this Pokemon master has what it takes to battle and beat the best trainers, as her crown is indicative of her talent above all else