My definition goes as follows: any effect that gives you access to two or more cards, either right now or over time
Red's strengths are sacrificing resources for great power, dealing direct damage to players or creatures, and destroying artifacts and lands
Meanwhile, Song-Mad Treachery is a card I really like for a reason similar to Pelakka Predation: people don't expect non-sacrifice decks to have Threaten effects, which means that Song-Mad Treachery can lead to some massive blowouts by stealing an unsuspecting opponent's best creature and smashing them with it
Quality of service, shipping speed, and packaging care can vary significantly between sellers
To add even more edge cases, Word of Command allows you to mandate and alternative casting costs are paid
If there is no Lesson card in your graveyard when Dragonfly Swarm dies, the ability will not be put on the stack at all