Spellcasting Focus

Rare

Use this book for spellcasting and unleash chaotic necromancy with each spell cast.   This focus occasionally summons aggressive undead into a space within 5ft. of a spell's target. Aggressive undead will attack the closest target and have no allies.   If using this item as a spellcasting focus, roll 1d6 at the start of combat to determine the effects as follows:

d6	Effect
1	Summon 1 skeleton each time a spell is cast
2	+2 necrotic damage to damaging spells
3	+3 necrotic damage to damaging spells
4	Add 4 temporary hit points to any target of a healing spell
5	All spell damage becomes necrotic and is doubled
6	Summon 1d10 ghouls each time a spell is cast

This tome appears to have a face wincing in pain on its cover. Instead of a clasp or strap, the book is sealed by a nail driven through the mouth of its face.