Despite all this it is clunky, is only one way with the synergies and offers something you don't really lack in the archetype
Instead of monsters, you can use continuous spell and trap cards as tribute
And I'd rather exile it (Karn) or do it for 5 mana (Vraska) than gain a bit of life from it
Japanese booster boxes are almost always guaranteed to include at least one card which is a Super Rare or higher rarity (including Ultra Rares and Special Art Rares)
These cards are so sought-after because of their rarity, so a collector having multiple thousands of the rarest in perfect condition from a single set (and a set which, as we'll come to, has its own controversy over the rare cards) was bound to raise some eyebrows: And sure enough, it did
Its virtually free if you stick it, and it lets you hold mana up after stealing an opponents creature