Can static illusions be cast on and move with moving objects?
As a 20th-level Illusionist Wizard, I can make an illusion of:
- a functioning volcano (Mirage Arcane)
- or a ferocious monster (Major Image)
- that can even deal damage (Phantasmal Force)
But using an illusion spell, can I, for example:
- put an illusory sweater on my dog?
- put an illusory blade on the end of my normal wooden staff that follows the staff even while I use it? (it would look scary!)
- put an illusory vase on a table, which moves with the table if the table is pushed? (it wouldn't get knocked over, of course)
Note: This question is about the general function and utility of illusion spells as a school of spells in 5e rather than about a specific spell. If specific illusion spells give different answers, that is a valuable part of the answer to this question.
Illusions can be cast at a place on the ground, and they stay there unless the spell gives you the ability to move them.
If the ground moves, does the illusion move? Does the D&D world spin like Earth does or fly through space? If so, the illusion usually moves with the ground on which it was cast.
Can an illusion spell such as Minor Illusion or Silent Image be cast on an object such as a sword or a table? If that object is then moved, does the illusion move with it? What about an illusory hat on my ally's head?
Put another way, what is the reference frame in which an illusion is cast, and is this something the caster can choose?
Clarification: I am not asking if I can pick up an illusion and move it, only if the illusion can be attached to something other than a fixed point on the ground and what happens when that something moves. A Minor Illusion would still be a simple, stationary object sort of illusion.