Sacrificial Dagger

This is a magical weapon and can be used as an arcane focus if it is attuned to by a spellcaster. It gives its wielder a +1 bonus to spell attack rolls and their spell save DC.

Whether attuned or not, a spellcaster may use the dagger in ritual casting twice per day. By inflicting 1d4 piercing damage to themselves, they may cast the ritual spell with its normal casting time, ignoring the additional 10 minute time requirement that ritual casting normally stacks onto the spell. This ability is refreshed to two uses after a long rest.

If attuned to by a spellcaster, as a bonus action and as part of casting a spell of 1st level or higher, you may deal 1d4 piercing damage to yourself and give yourself a +1 bonus to your spell attack or spell save DC for the spell cast. If you cast a spell that continuously requires saving throws, continue to use the bonus until that spell has been resisted or the spell has ended. Once you use this effect, you can’t use it again until you finish a short or long rest.