Does the Svirfneblin Magic feat use spell slots?

Question

Does the Svirfneblin Magic feat use spell slots?

The description of the Svirfneblin Magic feat states:

You have inherited the innate spellcasting ability of your ancestors. This ability allows you to cast nondetection on yourself at will, without needing a material component. You can also cast each of the following spells once with this ability: blindness/deafness, blur, and disguise self.

You regain the ability to cast these spells when you finish a long rest.

I think I understand 'innate' as meaning it doesn't need to be in the spellbook/prepared because it's a racial feat for Deep Gnomes, but I'm not sure if that also means whether or they use a slot when cast.

Answer 1

At will indicates you do not need spell slots.

The rules for cantrips help clarify this language of “at will”:

A cantrip is a spell that can be cast at will, without using a spell slot and without being prepared in advance.

To be clear, the spells from the Svirfneblin Magic feat are not cantrips, but the rules for cantrips give us a clear understanding of what “at will” means with respect to spellcasting.

This is also obvious from the fact that being a spell caster is not a requirement of taking the feat. If the feat required using slots for casting the spells, it would list that as a requirement in some way. The Eldritch Adept feat from UA 2020: Feats, while not official material yet, gives an example of how this would look:

Prerequisite: Spellcasting or Pact Magic feature

This feat would be totally useless to classes without spell slots, unless you can cast the spells without them.

Innate Spellcasting means it doesn’t use spell slots

In the Monster Manual, the Innate Spellcasting trait is given a definition for NPCs:

A monster with the innate ability to cast spells has the Innate Spellcasting special trait. Unless noted otherwise, an innate spell of 1st level or higher is always cast at its lowest possible level and can't be cast at a higher level.

In contrast, the regular Spellcasting trait is described as follows:

A monster with the Spellcasting class feature has a spellcaster level and spell slots, which it uses to cast its spells of 1st level and higher. The spellcaster level is also used for any cantrips included in the feature.

Now, you aren’t an NPC, but this demonstrates the common rules understanding of Innate Spellcasting: no spell slots necessary.

Answer 2

No, because you cast the spell "with the ability"

When a spellcasting feature requires the use of a spell slot, it always states that explicitly. For instance, the wizard's Spellcasting feature says:

The Wizard table shows how many spell slots you have to cast your wizard spells of 1st level and higher. To cast one of these spells, you must expend a slot of the spell’s level or higher.

As another example, the warlock's Pact Magic feature states:

To cast one of your warlock spells of 1st level or higher, you must expend a spell slot.

And some of the warlock's eldritch invocations grant access to more spells, often requiring the use of a spell slot. For instance, the Sign of Ill Omen invocation's description reads:

You can cast bestow curse once using a warlock spell slot. You can’t do so again until you finish a long rest.

However, other abilities (such as the Svirfneblin Magic feat) can cast spells without requiring spell slots, instead only having a daily limit on uses or requiring some other specified resource. If the feature simply says you have the ability to cast a spell once, you can just cast that spell, regardless of whether or not you have a spell slot that would be appropriate for the spell normally - or whether you even have spell slots at all!

Answer 3

The prerequisites for the feat don't mention being able to cast a spell as a necessary requirement. From that you can infer that non-caster classes, as long as they are Gnomes, can gain this feat.

Therefore, spell slots are not required.

There are many feats that make the distinction clear by stating "you can cast once without expending a spell slot". Again, the Svirfneblin Magic feat makes no reference to spell slots and so none are required to cast the acquired spells once per day or at will in the case of Nondetection.