Four toughness was already an important breakpoint in the format due to the various Dragons, and it seems like Hinata, Dawn-Crowned is about to make killing a four-toughness creature on sight and cheaply even more important
You can play riffs off Coffers like Cabal Stronghold and Nykthos, Shrine to Nyx, but nothing beats the original when you've built your deck correctly
Instead of just being the strongest or most efficient options, here are my five picks for Investigate cards that make the mechanic feel especially interesting, flavorful, and/or memorable: 5
Red and white by comparison are pretty lackluster on this front and will largely be reliant on raw aggression or access to other colors to present a cohesive 75 against the format, and may need both to keep up
Subgrades: Centering 9, Corners 8, Edges 9, Surface 8.5
But what does our Ol' Canucklehead do