so the idea is to have an item that once attuned will allow you to support 1 more concentration spell, which would open up alot for spell casters i feel like
Only being able to have 1 concentration spell in effect at a time is one of the major bits of rules that this edition hangs its balance upon, so it is something which should only be altered with either careful consideration of the potential effects (i.e. look at all of the concentration spells a class that could attune to the hypothetical item has and see what combinations can do - though the combinations themselves aren't necessarily broken, it's just important to consider the difference between the combo being possible without another character's assistance), or with deliberate abandonment of the current level of balance the game has.
As a DM, I'm strongly opposed to things which circumvent the 1-at-a-time portion of the concentration rules because I think combos like fly and greater invisibility are fine when they are coming from two sources (and presumably an opponent could end concentration upon one of the two without having to hit the invisible creature), but are unbalanced from the point of view of both non-spellcaster characters' relative potency (i.e. it makes it easier for other players to feel like their character is the spell-caster's "sidekick" rather than their equal partner) and players' having the tactic used against their characters amplifying the already true case that the rules favor monsters over PCs (such as spell slots for PCs assuming use over multiple encounters, but monsters can afford to burn every possible slot as quickly as possible since they are usually in a position that only this one encounter will exist for them).
The school of a spell doesn't really play into this conversation. I suggest limiting either the time of dual concentration to no more than a minute, or the sum of the level of the spells to be no greater than six.
"The relevant equation is: Knowledge = power = energy = matter = mass; a good bookshop is just a genteel Black Hole that knows how to read." - Terry Pratchett
If you possess a copy of Matthew Mercer's Tal'Dorei Campaign Setting, there is a feat there, called Dual-Focused. Basically what it does is: You can mantain 2 concentration spells at once. If you take damage, u make 2 separate concentration checks. At the end of each turn of dual-focusing, you make a conc. check DC=8+sum of spell levels. If u fail, both vanish, if u succeed, u keep both. I think it works pretty well mechanically, we are using it and it does work well, especially because it allows u to mantain 2 low-level spells with ease if you have like Battle Mage and a nice Con save, but without being overpowered.
I suggest limiting either the time of dual concentration to no more than a minute, or the sum of the level of the spells to be no greater than six.
The problem with the "no more than a minute" thing is, if you are in combat, you can do whatever because a minute is much longer than most fights last (unless there is something strange going on).
so the idea is to have an item that once attuned will allow you to support 1 more concentration spell, which would open up alot for spell casters i feel like
thoughts?
Only being able to have 1 concentration spell in effect at a time is one of the major bits of rules that this edition hangs its balance upon, so it is something which should only be altered with either careful consideration of the potential effects (i.e. look at all of the concentration spells a class that could attune to the hypothetical item has and see what combinations can do - though the combinations themselves aren't necessarily broken, it's just important to consider the difference between the combo being possible without another character's assistance), or with deliberate abandonment of the current level of balance the game has.
As a DM, I'm strongly opposed to things which circumvent the 1-at-a-time portion of the concentration rules because I think combos like fly and greater invisibility are fine when they are coming from two sources (and presumably an opponent could end concentration upon one of the two without having to hit the invisible creature), but are unbalanced from the point of view of both non-spellcaster characters' relative potency (i.e. it makes it easier for other players to feel like their character is the spell-caster's "sidekick" rather than their equal partner) and players' having the tactic used against their characters amplifying the already true case that the rules favor monsters over PCs (such as spell slots for PCs assuming use over multiple encounters, but monsters can afford to burn every possible slot as quickly as possible since they are usually in a position that only this one encounter will exist for them).
obviusly an item like this is not something that would be introduced before "tier 3".
there could be a limit on the spell lvl or school of spell the item could concentrate on to limit the abuseablity of it
The school of a spell doesn't really play into this conversation. I suggest limiting either the time of dual concentration to no more than a minute, or the sum of the level of the spells to be no greater than six.
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Astromancer's Homebrew Assembly
"The relevant equation is: Knowledge = power = energy = matter = mass; a good bookshop is just a genteel Black Hole that knows how to read." - Terry Pratchett
If you possess a copy of Matthew Mercer's Tal'Dorei Campaign Setting, there is a feat there, called Dual-Focused. Basically what it does is: You can mantain 2 concentration spells at once. If you take damage, u make 2 separate concentration checks. At the end of each turn of dual-focusing, you make a conc. check DC=8+sum of spell levels. If u fail, both vanish, if u succeed, u keep both. I think it works pretty well mechanically, we are using it and it does work well, especially because it allows u to mantain 2 low-level spells with ease if you have like Battle Mage and a nice Con save, but without being overpowered.
You could do something along those lines I think.
that sounds pretty interesting