Can Mage Hand be used to scribe the circle of blood used in the Summon Lesser Demons and Summon Greater Demon spells?

Question

The spells summon lesser demons and summon greater demon from Xanathar's Guide to Everything both say:

As part of casting the spell, you can form a circle on the ground with the blood used as a material component. The circle is large enough to encompass your space. While the spell lasts, the summoned demon can’t cross the circle or harm it, and it can’t target anyone within it. Using the material component in this manner consumes it when the spell ends.

While it doesn't specify where the circle is, the obvious intent is that you're drawing it around yourself.

That said, if you had cast mage hand and used it to hold the vial of blood, would it be possible to draw the protective circle at a distance of up to 30ft?

Answer 1

No, because both spells use your action.

You need an action to cast Mage hand and another to control it.

Casting Time: 1 action […] You can use your action to control the hand.

You also need an action to cast Summon Lesser (or Greater) Demons. Drawing the circle is only a part of that action.

As part of casting the spell, you can form a circle on the ground with the blood used as a material component.

Your mage hand wouldn't be dismissed, but it would just do nothing while you cast your Summon spell.

Answer 2

No, mage hand can't be used to cast spells

The vial of blood and using it in that way are spell components. Spell components have to be performed by the caster, or the spell isn't cast. Having a mage hand do any part of spell components means you're not performing and handling the spell components, and the spell fails.

Even if you could make the action economy work, mage hand simply doesn't qualify as the caster's own hand.

Answer 3

No. Controlling Mage Hand Requires an Action.

You need that action to cast the summoning spell.

You can use your action to control the hand.

With Haste: Still No

The haste action is limited as to what can be done with it.

That action can be used only to take the Attack (one weapon attack only), Dash, Disengage, Hide, or Use an Object action.

Answer 4

Slightly possible, as an Arcane Trickster

The issue is, Mage Hand and the spells you suggested both require an action, so they aren't naturally able to be cast/used at the same time. However, there are ways to cast/use Mage Hand without interfering with your action. A solid example is the Rogue archetype, Arcane Trickster.

The Arcane Trickster Rogue class feature, Mage Hand Legerdemain:

Starting at 3rd level, when you cast Mage Hand, you can make the spectral hand invisible[...] In addition, you can use the bonus action granted by your Cunning Action to control the hand.

The cantrip Mage Hand:

[...] You can move the hand up to 30 feet at a time. [...]

This would mean that you could move the Mage Hand into a 30 foot circumference circle without interfering with your action. This roughly translates to a 5 foot radius (exact amount is a 4.8 foot radius).

Since Mage Hand has a 30 foot range, you don't need to be in the center of the circle it draws. A 5 foot radius would make something akin to a 2x2 square.

Answer 5

Yes you can.

But only if this is a thematic use (the circle is still inscribed around you, but instead of you bending down to inscribe the circle, you have your mage hand that was floating beside you inscribe it around you instead).

Because so long as you don't change the effect of the spell (creating the circle at a range, instead of around you), then everything else is just thematic sugar meant to make casting the spell look cool.