what is a side deck yugioh are good options for Yu-Gi-Oh deck? How to build a side

Through various other mechanics, especially with regards to Hardened Scales strategies, theres plenty of room to combo out with the Walker

Soul Separator brings him back for another number

Case Study 2: You want to climb the Constructed ladder for this season (and for sure to clear quests and/or to gain XP), but you either don't have enough wildcards to complete the deck you want to play or its near rotation whereby spending wildcards might not be worth it

By using this card, Yusei would not only prevent his opponent from gaining the advantage during the duel, but he would also bypass the summoning requirements of his iconic signature monster