This can be pretty difficult to pull off, but even dealing 1 or 2 damage is enough to cast powerful and cheap spells like Demonic Tutor
This card's price has seen some moderate fluctuation since its release, but overall, it has steadily increased in value over the last few months
2: Create a 1/1 red Devil creature token with When this token dies, it deals 1 damage to any target. 7: Target player draws seven cards and loses 7 life
While its nice to use those treasures for generating mana, why not use them to generate damage instead
Jellicent ex Best Psychic-type disruptor to lockdown the meta
It generates energy counters equal to the number of nonbasic lands an opponent controls when it comes into play, and then allows you to spend four energy to destroy a nonbasic land and make nonflying creatures unable to block each time it attacks