House Rules
Generally, the official 2024 D&D 5E rules are followed to the letter (or number) as closely as possible, unless there is really good reason not to.
The "Rule of Cool" absolutely fully applies to story, character, flavor, and everything outside the rules—but to me, to "Calvin-Ball" it and change the rules on the fly is to lessen the stakes, challenge, fun, and even authenticity of the experience as a game that involves rolling dice and all that.
That said, "House Rules" are something different—these are established and agreed-upon from the outset.
Mine are few:
CHARACTER CREATION
I'll review every character and suggest or make adjustments to fit the setting best, maintain some degree of balance/challenge, or any other reason. (I'm fair.) I'll assign magic items, gold, etc. after you've built and "turned in" your character.
Ask me before choosing changeling or a flying species. They might not be right for the game in question. (Of course, if you wish to make an aarakocra who can't fly—with clipped or hacked-off wings (hella backstory fodder there, damn!), for example, no need to ask.)
Generally, if you can build it on D&D Beyond (I have and can share any of the content on there), it should be good, assuming you aren't trying to downright exploit it. No laser-rifles, for example (nice try!).
I love to see character sheets filled out with the details but that's all optional. And of course your chosen Allies, etc. need to be reasonable.
Feel free to ask if you're ever unsure on anything throughout the process. I'd rather you check first than fall in love with something that we might need to change later. I'm also happy to build a character with you step-by-step, or to make one for you if that's your preference.
MATURE CONTENT
I generally use MPAA movie-rating system in my ads for games. Most will be "PG-13" to "R," involving mature themes like death, disease, subjugation, horrific creatures and events, and the like. Torture and sex will be "fade to black" moments with nothing happening "on-screen."
If you can't handle something that is happening during the game, please feel free to drop out of the session immediately. It's just a game. If you are triggered by the mere thought of spiders, blood or any other such specific subject that could be expected to be found in any horror, sci-fi or fantasy film, I'm probably not the DM for you.
OTHER THOUGHTS
I urge you to embrace a character's death, if it happens. It builds good... character. (In more ways than one.)
That said: Once again, this is fantasy and no one need stay dead forever. Not only are there forms of magic out there that can resurrect and reincarnate, there are countless other strange ways your character might live on. Their soul might infuse a new body, perhaps a construct of some sort. They might be raised again as a Reborn or reincarnated more, uh,... naturally?...as an aasimar or tiefling or genasi, or even their own descendant further down the line.
Another thing to think about is that, in most cases, per the rules, a soul must be willing to return to our world after they've crossed over to the other side. And when you realize that good-aligned characters tend to go on to a literal paradise after death, seeing their own departed loved ones again in some idyllic land of perfection in their own god's realm—places like Mount Celestia and Arborea and Elysium—and knowing that in time the ones they left behind would eventually join them—soon, even, given this context... that awakening might compel their souls to remain in the Afterlife and patiently wait. That is unless, of course, they have left behind some vital mission yet unfinished, a clock that remains ticking, some drive to go on. In such cases, they very well may choose to leave Paradise behind and return again to our hard, cold reality.
As for evil characters, though, it's a different story. Their afterlives are, to no surprise in this setting, hellish. They will understandably likely jump at the chance to come back from the other side—and, now having had a first-hand experience of what awaits them in the Nine Hells or Acheron or Gehenna or The Abyss—those evil souls might try damn hard to change their ways with this second chance at life (a justification to change a formerly evil character good; even warranting a class change at that point!). Unless, of course, they see being a hideous soul-larva or lemure for centuries as a price they're willing to climb the ranks as a Fiend, choosing not to return to the world of the living.
In other words, death need not be final in these kinds of games, but should also be embraced. (In this game and not in real life, to be clear; in reality life should be celebrated and preserved at all reasonable cost). That's part of the fun of these games, that we can explore things we are better off leaving behind in our own lives and world. It's a space where you can get those things out of your system. But always remember it's a game. Think of it as a version of poker night, Monopoly Night, movie night, but all those things combined and so much more.
I'm totally open to any other home brew rules or general thoughts, just drop me a line!