Some produce energy as a triggered ability, such as when they attack or deal damage, and in Jeskai, you've also got access to a lot of effects to exile and return permanents to play, providing you with opportunities to get energy multiple times
Outlaws of Thunder Junction This set may have been a bit of a mess flavorfully, but Outlaws of Thunder Junction and its ancillary set, The Big Score , are home to some very important Standard cards
This is especially useful on a battle because it can allow you to remove a blocker to let you attack the battle right away
Thats all
Turn 3 and 4 kills were common, and the format is full of these snowballing threats that will take over the game in a short matter of time if you can't kill them immediately
"Permanents" stay in play after they are played, and their effects stay as well