Bloodfont
Weapon (dagger), very rare (requires attunement by a sorcerer)
Bloodfont is made from a shimmering crystal dredged from deep within a long-tapped mine.
While attuned to this dagger, it is also a spellcasting focus for you. It has 12 charges, and it regains 1d10 + 2 expended charges daily at dawn. When you use a feature that requires you to expend sorcery points, you can also expend charges from the dagger. For each charge expended, you reduce that feature's sorcery point cost by 1 for this use.
Additionally, when you start your turn with hit points equal to or less than half your hit point maximum, you can use a bonus action to coat the blade in your magical blood. While coated in this way, you can cast any spell on the sorcerer spell list from it, regardless of whether you know it. When you cast a spell this way, you expend a number of charges equal to twice the spell's level, and the spell doesn't require verbal or somatic components for you, though it still uses your spellcasting ability.
Fiend Fane
Weapon (mace), rare (requires attunement by a warlock)
Fiend Fane is a magical mace forged of condensed souls from the Nine Hells
You gain a +1 bonus to attack and damage rolls made with this magic weapon. In addition, if you have the Improved Pact Weapon feature, you gain a +1 bonus to spell attack rolls made with weapon while it is your spellcasting focus.
While attuned to this weapon, you gain the Devil's Sight Invocation. This invocation doesn't count toward your number of Eldritch Invocations known.
Shredder
Weapon (handaxe), uncommon (requires attunement by a bard)
You gain a +1 bonus to attack and damage rolls made with this magic weapon.
While attuned, it counts as a musical instrument with which you are proficient, and you can use it as a spellcasting focus for your bard spells. In addition, when you perform with it using your Song of Rest feature, each creature that would benefit regains the maximum number of additional hit points instead of rolling an extra die.
Tower
Weapon (quarterstaff), legendary (requires attunement by a wizard)
While unattuned, this quarterstaff has an unassuming appearance, looking like any other. When attuned, however, Tower takes an appearance that complements that of your spellbook. For some, this may be a stone spire inscribed with thousands of runes, which represent the spells in that spellbook, or for others, a scroll rolled impossibly tight.
You gain a +3 bonus to attack and damage rolls made with this staff. While holding it, you gain a +3 to spell attack rolls, and it is an arcane staff.
While attuned to Tower, it is considered a spellbook for you. If your spellbook is lost or destroyed, Tower magically absorbs the spells written within it, and you can transcribe them from Tower into another spellbook for no cost.
Additionally, when you use your Arcane Recovery feature, the spell slots you recover can have a combined level equal to 2 + half your wizard level (rounded up). These spells must still be of 5th level or lower.