Random ideas that I couldn’t figure out how they would actually work. Feel free to take any or all of these seedlings for any purpose.
Cursed magic items that infect magic items around them. Maybe they leech into them, stealing their power to fuel an ability or something? Maybe that is the catalyst of something, like an Ice-9 of magic, spreading from magic item to magic item, mage to mage, making them unstable or unable to cast.
Magic items and curses with campaign level rewards or penalties. This seems easy enough, oh, you get a +5% bonus to production/taxes/armies, but how to make it fun for a tabletop game rather than accounting/map simulator? I have those already. Spells usable over a wide area/domain seem interesting, but also hard to hit the knife-edge of useful but not overpowered.
Get your spell components out of my game Wizards of the Coast. Your stupid puns and inside jokes are whatever, but they clutter everything up. Put in the work to actual make a clever or engaging spell component system or just treat spell component pouches/wands/holy symbols as a tool and be done with it. I could do this one, but it would be so fiddly. I’d rather just complain and occasionally make up limited use special components that give bonuses.
Cursed summoning templates? If you keep sending so many summoned creatures to die or violate their moral code or just piss off the ruler of the plane they come from, you can get cursed. Attribute penalties seem too boring, oh a -2 to this roll or fewer summoned creature hit points, blah. The fun kind of curses are having to throw salt over your shoulder when a trigger condition is met or a summoned creature that follows you around eating all your food until you prepare spells again but if you kill it or get it killed the curse gets worse. They are just punishments to not use summoned creature spells that are already not that great in fifth edition anyway. That and having to come up with enough flavorful curses, likely around the type of creature is so much work for so little payoff. Curses are annoying anyways, as I have to remember to apply them, I’d rather have conditional bonuses that the players have to remember and jump through hoops to get.
For that matter, what about cursed spell templates?
Using exhaustion levels as a stand-in/abstraction for a more complicated injury system. I don’t necessarily like the fixed exhaustion effects per level so I could see doing something like a debilitating list that is picked from. I also like this random idea of either doing it as the defender picks or the attacker picks 2 with 1 vetoed by the defender. Maybe on a natural 1, the attacker picks 3 and defender vetoes 1? That sorta just works out to the attacker always picking death plus one or two others so the defender always just vetoes death. Maybe Death is like the 8-ball, in that it can’t be picked until last?
So between the lockpicking lawyer videos I’ve watched lately, playing skyrim with its incredulously unlooted tombs, and various discussions of lock defeating methods (social engineering, kicking in a door, shimming etc) has reawakened my discomfort with tomb locks. How do you get a logical in game lock that hasn’t been defeated? Especially in the presence of magic or angle grinders, the real deterrent to locks are that they delay you and are noticeable enough that armed guards stop you. That can’t generally be the case for the kinds of dungeons that are regularly plumbed by adventurers, and arbitrarily blocking access to places is the kind of solution that tedious and realism breaking video game use. It seems a little hokey, but what if failures on lockpicking didn’t prevent progress but merely allowed the DM to either inflict a penalty or offer a choice. The penalties probably shouldn’t just be things like traps triggering as an HP tax or flat negatives to rolls, as those are boring and leave little for the players to engage with. Something akin to the DM taking a hard-move per the Powered by the Apocalypse games, something happens to advance enemy plots or detract from the players’ goals. What if we expanded that system to roll up wandering monster checks, which don’t always apply in abandoned places, cleared out dungeons, or times that it simply doesn’t make sense to have some new monster bumble in. Maybe that should be the cost of time, is the players risking bumping up an enemy’s track or losing their own progress on something. It wouldn’t take too much to abstract this in either, the time they spend wandering around uselessly picking locks or trying every combination in a puzzle is time the rest of the world keeps moving. It should happen anyway, but putting it directly into the game serves as a direct reminder for the DM to advance other events and show the players exactly when those things are happening. What if some quests and plotlines in video games had small ticking timers that advanced not by an in-game clock but by the times you failed?