Enter Burrenton Forge-Tender
Base Set 102 cards Jungle 64 cards Fossil 62 cards Team Rocket 83 cards Gym Heroes 132 cards Gym Challenge 132 cards Neo Genesis 111 cards Neo Discovery 75 cards Neo Revelation 66 cards Neo Destiny 113 cards Total 940 cards Are all 1999 Pokemon cards 1st Edition
Usually, sideboards need to reserve some space for Artifact, and Enchantment removal effects, but Boseiju allows such effects to be run in the main deck
You play them, get an immediate effect worth a card (thats possibly a bit overcosted, since theres a potential second benefit coming later), and then have the option to defeat them
In fact, in Legacy, I board it in against both Death and Taxes and Jeskai Control even though neither deck really interacts with their graveyard, simply for the previously mentioned reasons