Cards that generate additional mana, like Mana Reflection, Mirari's Wake, and Nyxbloom Ancient, can help accelerate your mana production and enable you to cast this powerful monster and other devastating ones like Avenger of Zendikar
This card also has the Victory Pose ability, which states that during your turn, whenever this character banishes another character in a challenge, you gain two lore
Although higher numbers of Endurances are found in sideboards than in the maindeck, I wouldnt be surprised if decks include more Endurances maindeck already considering how much flexibility this card gives
Boseiju can deal with such threats like Underworld Breach, Esper Sentinel, Counterbalance, Mystic Remora, and so many others
Four mana for a one-sided Howling Mine is already not the worst place to start, although that on its own would hardly be impressive
Its a great way to revisit the seriess biggest moments while still getting a booster format built for actual play