I always thought that braces had such a constricting and caged look that felt fitting for the creepy feeling of the prompt
You choose which player, planeswalker, or battle the Human is attacking
Similarly, if you sacrifice a creature to activate a mana ability while activating Heirloom Epic's ability, that creature won't be on the battlefield when you pay the ability's activation cost, so you won't be able to tap that creature rather than pay one of the mana in the activation cost
Subsequently, a Meld card that can Meld again to create an even bigger creature is potentially a better solution than Dual Masters 3D Dragsolution
Apparently not a Colonel in this timeline, this Ravnica: Clue Edition commander grants a host of useful abilities to your other soldiers, and has an interesting ping ability that it can bestow on your attacking soldiers
It also introduces a new design for full-art shiny variants