We look first at Commander (since it's the most played format on tabletop MTG) and Standard (given it's the most popular format in MTG Arena), although of course removal spells that are multi-format staples and show up in Modern, Pioneer, or Legacy will get a nudge
Barring the occasional comedic misfortune, its hard to top the value this tutor can provide
[207] The most expensive card that was in regular print, versus a promotional or special printing, is the Black Lotus, which are today valued at thousands of dollars
With enough mana you can cast these over and over, bouncing themselves back to your hand, and churning out 4/4 Zombie tokens each time
The water and grass halves of the holo big three
Archangel of Wrath prevents all of that aggressive nonsense thanks to lifelink and her kicker trigger