Like most Magic: The Gathering cards, the value of Guide of Souls depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Modern Horizons 3)
some were unblockable, some had deathtouch, some had Curiosity effects built in, but there was no real cohesion
Every non-Core Set since Arabian Nights, released in December 1993, has an expansion symbol, though the changing of the color for rarity didnt start until Exodus, released in June 1998
On top of that, you can play with other players whenever you want
Just play Spectacular Pileup, which gets around Heroic Intervention, and then cycle it if you draw it late and you dont want to cast it
Beyond being a sheer card advantage engine, Azami also has some very achievable combo finishes: Isochron Scepter plus Dramatic Reversal is the tried-and-true combo line to untap all your mana rocks and Creatures repeatedly and adding Azami to the mix turns those untapped Wizards into unending card draw each loop
