Like most cycles, some of these are better in Commander, and some of these are better in certain decks or metas
Then the duo of Slimefoot and Squee turns four mana and a saproling into a reanimated creature: this great Jund card is part of some of Jund's best combos
Then, once you hit twelve loyalty counters on a planeswalker (ideally more than that, so you can keep your planeswalker), you can take an extra turn
It's still getting charge counters whenever the equipped creature deals combat damage, and the charge counter persists even if the equipped creature dies or it gets equipped to another creature
For instance, Lorehold makes a 3/2 Spirit creature token, and the Collector Booster is where you get it in foil
It starts small but grows with each color among permanents you control, adding 1 mana of each color represented