Unfortunately, mystic arcanum does not allow picking a lower level spell and upcasting it. The spellcasting rules in the PHB state that when a spell is upcast at a higher level, it’s treated as a spell of that level.
Can warlocks cast spells at lower level?
You cannot cast spells at a lower spell slot. Having a couple level 1 slots to play around with is a fun option since the very nature of the Warlock class is few spell slots but at high levels.
Does Mystic Arcanum require spell components?
Mystic Arcanum only excuses the spell slot requirement. You can cast your arcanum spell once without expending a spell slot. You must finish a long rest before you can do so again.
Does Mystic Arcanum count against Warlock spells known?
No, the warlock’s Pact Magic feature is a completely separate feature from the Mystic Arcanum feature, and each independently describes how you get spells without relying on or referring to the other. Pact Magic says you get another spell known at e.g. 11th level, so you do, period.
Can you use mystic Arcanum more than once?
Mystic Arcanum literally says: You can cast your arcanum spell once without expending a spell slot. You must finish a long rest before you can do so again.
Can I Upcast Mystic Arcanum?
Warlocks get Mystic Arcanum, not spell slots, for levels 6-9. By rule, then, can’t upcast for stronger creatures.
What level do warlocks cast at?
Cantrips are not subject to the spell-level mechanics like your spells. They were considered 0-level-spells before however 5e cantrips are different and they can be used as simple cantrips. However rest of the warlock spells are cast at the highest spell level because that is the only spell slot the warlock has.
Can you change Mystic Arcanum?
No. It’s because it isn’t actually a spell slot, it’s a class feature that only lets you use the selected appropriate level warlock spell.
Can a warlock know more than one mystic Arcanum spell?
A spell you choose must be of a level no higher than what’s shown in the table’s Slot Level column for your level. The Slot Level column never increases above “5th”, so a warlock can never know a warlock spell of 6th level or higher. Therefore the Mystic Arcanum spells must be known separately from the warlock’s Pact Magic spells.
Where do you find spells known in Warlock?
The Spells Known column of the Warlock table shows when you learn more warlock spells of your choice of 1st level and higher. A spell you choose must be of a level no higher than what’s shown in the table’s Slot Level column for your level.
Is the Mystic Arcanum the same as Pact magic?
If that reasoning is not convincing, here’s a bit of circumstantial evidence underlining the necessary separation of the two features: Notice that the spells you gain access to with Pact Magic and Mystic Arcanum cannot be the same due to incompatible spell levels!
What does mystic Arcanum do in RuneScape?
The Mystic Arcanum feature, separately, gives you access to a new spell that you can use with the Mystic Arcanum feature.
