You could build a power board: a 15-20 card sideboard that can slot into a deck specifically to change the power level only
, : For each creature token you control, create a token that's a copy of that creature
Kashtira Fenrir, Kashtira Unicorn and Kashtira Ogre will all mess up the opponent's resources, even though the Mitsurugi Deck does not make use of the Extra Deck compared to the more meta decks
Legendary Planeswalker - Sorin Voldaren Bloodcaster Flying Whenever this creature or another nontoken creature you control dies, create a Blood token
Every time its equipped creature deals combat damage, you get two charge counters, and each one can be spent to give your creature +2/+2, shrink an opponents creature by 1/1, or gain 2 life
During the climax of Jaden's Duel with Yugi Muto, Yami Yugi appears and takes over, who Special Summons "Slifer" from his Graveyard