The level up keyword may not be around anymore, but the theme has continued with cards like Ascendant Spirit, Warden of the First Tree, Evolved Sleeper, and Surge Engine
Rather than one clear strategy, this deck gives you a large number of options for overtaking your opponent
This often occurs through efficient exchanges, like casting Blightning, which costs you one card but forces your opponent to discard two
And this doesn't have the modern templating of "return target creature an opponent controls" as you can bounce your own thing
The -3 to Flameslash is not super-efficient, but it is quite hard-hitting and critically leaves Chandra with remaining loyalty if used right away
The Gateway kit is the perfect way to learn Lorcana The key is that Lorcanas Gateway Kit isnt just a bunch of cards, but instead a fully developed system that slowly builds up each players deck and options over time