@aeonsovarius Blazing Archon doesn't stop Walking Ballista and is much more annoying if it gets Metamorphed. The funny thing about Gisela is the damage reduction/increase occurs in parts and the person taking damage chooses the order in which they are applied. Gisela attacks into Gisela, apply damage reduction (5->2), then damage increase (2->4). Giselas bounce. Attack with 1/1 or ping with Ballista, apply damage reduction (1>0), then damage increase (0->0). MTGO does this optimally, but you should 100% know this interaction if playing in paper. It's non-intuitive, and you are allowed by the rules to screw it up (double damage, then half damage).
And yes, if your version is running 6 drops and Walkers, it was probably designed to become a control deck post-board against decks like Jeskai that are boarding in enchantment removal, cages, and preists.