And the Pikachu which would be 1/3rd decks (~16 or 17) can already be found in one collection (Ignore the top-left one, which is 1st edition
This leads to wonderful situations where you can have most of your board hopping around and allows for absurd combos like generating infinite mana with Peregrine Drake before milling out an opponent with Thought-Knot Seer
Commitment, that's why
The other is jumbo-sized cards that are physically slightly larger than the standard poker-size cards
4 There are, of course, other peaks, corresponding to other sets of design goals and cube architectures for example, a Vintage cube that supports Splinter Twin and Channel combos will have a different peak than a cube that has identical restrictions, but does not support combo
But that blocks diverse collection of multicolored cards, flexible lands, and powerhouse spells have since become staples in many Commander players favorite decks