cards like overrun mtg | Magic 2012 Nature doesnt walk. Overrun (2) LP Tempest MTG

If you can leverage this kind of effect, Static Orb and Hokori, Dust Drinker provide redundancy

The big cost with Study is the card disadvantage

For Death's Shadow, the average converted mana cost is incredibly low (likely the lowest in all of Modern) at 0.76, meaning the average nonland card in the deck costs significantly less than one mana

Its your journey, Precious, anything could happen

In the case of John Silver, Greedy Treasure Seeker - it really depends on how many locations you can play alongside the character

Bane Alley Blackguard Crypt Incursion Drown in Filth Fatal Fumes Hired Torturer Maze Abomination Morgue Burst Pilfered Plans Rakdos Drake Sinister Possession Tithe Drinker Ubul Sar Gatekeepers