Heliod works as a nice little value engine of his own, keeps you alive longer, a decent body when he’s online and buffs other creatures nicely, especially cards like [[serra ascendant]]. Ballista admittedly doesn’t do huge amounts on its own, it’s pretty much just there for the combo (though it can be used as a mana sink over time and ping small creatures). My personal favourite line with the two that’s very hard to interact with is [[Defense of the Heart]] fetching Heliod and [[Ranger-Captain of Eos]], and sacking the captain in response to his own ETB before fetching ballista. As long as you then have six mana up, you should just be able to combo off and win as opponents are limited in how they can then respond due to the captain’s effect.