Are Signature Spells limited to 3 total per deck, and does this limit include the champion itself?

Ruling: You can include a maximum of 3 total Signature cards in your deck. The champion itself does not count toward this limit because champions do not have the "Signature" card type.

Nuances:

• If a champion has multiple signature spells available, you can still only include 3 total signature cards (e.g., 2 copies of one signature spell and 1 copy of another)
• Only cards with the specific "Signature" type count toward the 3-card limit