Although you may want to include Lessons in your sideboard if you're playing with cards that instruct you learn, Lesson cards can be included in your main deck like other instant or sorcery cards.

The Lesson subtype has no special rules associated with it.

Lesson is a new spell subtype found on some instant and sorcery cards in this set.

Discarding a card and putting a Lesson card into your hand are both optional.

If instructed to learn, you may do nothing.

The official Commander rules don't include sideboards, but if you're using them anyway or casually allowing players to get cards from their collections, cards you bring into the game from outside the game can't share a name with any card in your starting deck.If you bring a card into the game from outside the game in a Sealed Deck or Booster Draft event, you may select only a card that is in the card pool that you built your deck from.In casual Constructed games, the card comes from your collection.

If you bring a card into the game from outside the game in a Constructed tournament (or a Constructed game played under tournament conditions), you may select only a card from your sideboard.

If a card is brought into the game from outside the game, it will stay in the game until it ends or until its owner leaves the game, whichever comes first.

If you didn’t discard a card, you may reveal a Lesson card you own from outside the game and put it into your hand.”

txt For Magic Online (MTGO): Download as MTGO. 701.45a “Learn” means “You may discard a card.Graveyard - Ashen Ghoul, Brain Freeze, Breakthrough, Cabal Therapy, Careful Study, Carrion Feeder.From the Comprehensive Rules (June 16, 2023- The Lord of the Rings: Tales of Middle-earth)

Mtg dredge casual