Pod decks use Birthing Pod or similar effects to sacrifice creatures and search for more expensive creatures, creating a carefully designed chain of toolbox targets. Each creature can therefore serve as both a useful card and a stepping stone towards something even better.
Restoration Angel and Karmic Guide provide useful value along those chains, while modern creature-toolbox decks can use cards such as Eldritch Evolution and Neoform to imitate Birthing Pod's basic premise.
