Yes, Isochron Scepter will imprint an instant card from your hand with the additional requirement that it must have a converted mana cost of two or less; it will then allow you to play that copy whenever you feel like by paying two generic mana and tapping the scepter.
There are a great deal of artifacts that interact with instants and clone them in a variety of different ways with different requirements and limitations.
Examples:
Panoptic Mirror
Isochron Scepter
Knowledge Pool
Mirrari
'Flash Counter' is a Blue Instant costing 1U. "Counter target instant spell."
Yes. As long as you qualify as a legal target for the spell, you can choose yourself as the target.
Any card that destroys a target artifact, or destroys all cards on the battlefield.
An Artifact Creature is simply a creature who is also an artifact. It is subject to all normal rules regarding both creatures and artifacts, and if a spell can be used against a creature or an artifact, it can be used on that creature.
If a creature has Intimidate, when it attacks, it can only be blocked by creatures that share a colour with it, or artifact creatures.
Creatures and artifact creatures have summoning sickness. Artifacts and creatures with haste do not have summoning sickness
The artifact creature 'Pentavus' can remove its +1/+1 counters to create 1/1 flying Pentavite tokens.
A permanent with shroud cannot be the target of spells or abilities.
i no of an artifact that lets you make a 1/1 of any color and creature type
Target should sell Magic cards, there may also be independent sellers in Tamworth.
There is no hard limit. You can use a 100% artifact deck if you wish. It might not necessarily be viable depending on format, but there are some artifact land, and some 0-cost artifacts that produce mana.
It looks like a ball on a stand. It is an image of Mirari, a powerful artifact that practically drove the events of several blocks and novels.