Siberys Mark of Storm

The Siberys Dragonmark of Storm provides the following benefits:

• Increase your Dexterity or Charisma score by 1, to a maximum of 20.
• You learn the planar binding spell and can cast it once without expending a spell slot. When you cast it with your Siberys mark in this way, its casting time becomes 10 minutes (as if casting a ritual spell), and it targets only elementals. You also learn the control weather spell and can cast it once without expending a spell slot. You regain the ability cast these two spells in this way when you finish a long rest. Charisma is your spellcasting ability for these spells.