What general abilities would Heart players have?

What abilities a Heart Player may get is also extremely dependant on their Class, but generally there’s a few things they all seem to share.

First of all you could argue Dirk being awake on Derse and Earth at the same time could be a trait Heart Players share, similar to Space Players waking early on Prospit, but there’s no confirmation about this being a general Heart Thing or merely a Dirk Thing. Still, it would be fitting for it to be a Heart thing. Heart Players also seem to build ‘personas’ for themselves, representatives of other facets of their selves or trying to accomplish some sort of ideal- Dirk making Brobot and Lil Hal, Nepeta’s roleplaying persona, Meulin trying to emulate the Meowrails with Horuss…

Heart is the opposite of Mind, where Mind tells us of how they present themselves outwardly, their choices and such, Heart speaks of the more intimate and personal aspects of a character. Their True Selves, their Soul. Romanticism, Affection, Passion, a Hero of Heart’s powers would be heavily related to others’ or their own feelings and desires, as well as their actual Soul. How they use this Aspect, of course, depends entirely on the Class.

As we see with Meulin, the Mage of Heart, she uses her deep knowledge of Relationships, Character Interpretation and Romance to match people together and make her Shipping Grid come to life. Dirk, as the Prince of Heart, struggles with his personas to the point he nearly Destroys Lil Hal. He shows at various points to be capable of tearing people’s literal Souls out of their bodies, and his toxic attitude damages his relationship with his friends pre-God Tier. Thankfully, as opposed to Bro being an unaware Shitbag in general, Dirk is way more aware of this and shows concern about his manipulative tendencies and wants to not be That Asshole™ and be a good friend.

You could also argue the fact Lord English can kill ghosts comes from the fact that he’s part AR, and thus part Prince of Heart- Literally part Destroyer of Souls, but really, with the power to tear Paradox Space itself apart, killing ghosts seems Trivial.

When Davepeta was formed, their existence sort of mixed and overwrote that of Davesprite and Nepeta- In a way, true to her Rogue of Heart nature, stealing both their Souls for their mutual benefit into a single, radical and way more content being. Davepeta is the one to pull off an Undertale Parody as well, Determination being, fittingly, Time + Heart, so one may also say the concept of the Soul from Undertale also ties in with Heart in Homestuck, inner strength, willpower…

In the end though, Heart is what you make it to be. As it relates to such broad concepts as the Soul and the True Self, it’s broad enough that pin-pointing a specific power set without a Class or without knowing the specific person is nigh impossible. Like most Aspects tend to be.