When you use a spell slot to cast a spell that animates or summons an Undead (including Animate Dead, Create Undead, or Summon Undead), you can expend the Charm (no action required) to treat the spell as if it were cast using a spell slot 1 level above the slot expended.
Manifest Charm of Mabar, the Endless Night
RewardEFAp. 502024
Raw data
{
"name": "Manifest Charm of Mabar, the Endless Night",
"page": 50,
"type": "Charm",
"__prop": "reward",
"source": "EFA",
"entries": [
"When you use a spell slot to cast a spell that animates or summons an Undead (including {@spell Animate Dead|XPHB}, {@spell Create Undead|XPHB}, or {@spell Summon Undead|XPHB}), you can expend the Charm (no action required) to treat the spell as if it were cast using a spell slot 1 level above the slot expended."
]
}