The created card doesn't necessarily need to be from your deck, library, or sideboard, and could be a card in another set or format, as if it was created "out of thin air"
Generous Ent Generous Ent makes the list because of the forestcycling ability
Once players know the basics, they can expand on the starter decks with new cards from booster packs, or even mix starter decks together, keeping in mind the rule of a minimum of 60 cards and only one or two ink types per deck
Saying this fills your quota of one-mana cards isn't true at all
Any creature-heavy deck looking for protection from targeted removal should consider trying out Shalai
Other than merfolk kindred decks, Deeproot Historian might be worth a look as a way to ignore commander tax for any deck with a druid in the Command Zone: Faldorn, Rashmi, Chulane, Kinnan and Tatyova are good homes, just to name a few