The hope was that every card should represent something that is memorable to someone
An invisible ink card is a special variant of the regular version, that basically looks the same, but is exclusively foil and has extra in-universe text from the investigative crew taking notes about the character
Supposed to be with MTG back (to be verified)
There are a ton of very powerful WizardsArcanis the Omnipotent, Memnarch, Ambassador Laquatus, Trinket Mage, Niv-Mizzet, the Firemind, Teferi, Mage of Zhalfir, Venser, Shaper Savant, and more
Less cute is the sandworm with its dune vibes and the creepy swamp card
Unlike Wellwisher this doesn't need any infrastructure to work, and it doesn't tap, so you can attack, block, grab equipment, and more