New Magic Weapon Idea

[AngryJesusMan]

I'm a little late to this party, but I wanted to chime in while I had the time and was thinking about it.

The way I’ve worked magic items that get more powerful with characters in a game is pretty formulaic, because that's the kind of person that I am and my players accept that.

First, once a character has bonded with a weapon and isn’t in Conflict, give it a bonus to attack and damage equal to half of the character’s proficiency modifier, rounding down. That grants +1 from level 1 to 8, +2 from level 9 to 16, and +3 at 17th level and higher. It sticks to basic character progression, so it shouldn’t unbalance anything by granting too heavy a bonus too early. (Though, admittedly, a +2 at level 9 through 11 may seem a little high in my mind. Your game means you can do whatever you want with it.)

Second, give it a fairly powerful ability. I’ve used commune or commune with nature in the past, but this can be anything that gives the item a personal amount of flavor and fits with its theme. I've made this ability able to be used at no cost to the user, but made it usable something like once a week. That gives the player something to use beyond the basic magic weapon format and maybe gives the DM a means by which to provide plot. If you want to go with something less powerful, you could make it usable more often. This is where your personal tastes come into play. If you don't want to use it for plot dissemination (which worked for my campaign, but maybe not for yours), then any ability becomes a possibility, and there are any number of abilities that may be far more fitting for the flavor of the weapon you're creating.

Finally, if you’re going to give the item charges, give it a maximum number of charges equal to the character’s level. Then, if it grants spells that can be cast with charges, make each spell cost a number of charges equal to twice the level of the spell. That means that, even if you make a weapon capable of casting 9th level spells, the character can’t build enough charges to actually cast that 9th level spell until they've reached 18th level, which is about when a spellcaster gets access to that level of spells anyway. It means that players might be tantalized by the power in their grasp and stay true to the weapon even when they're in a lull between big spells, but also they might have a few more charges to use the smaller spells.

This means that you, by default, have some rough tiers built into the weapon, but it's improving with them every step of the way if they have charges that grow with their level. It's worked fairly well in my campaign and I thought it might do you some good. Hope it helps!