Foci for magical effects

"As a general assumption, it can be stipulated that all magic which is not of ritualistic nature requires some kind of focus."
From "The introduction to a Systemic Approach on Magics (SAM)" Collegium Magica, Magistra H'leria 1236 p.fl.

The Magistra is quite correct and quite wrong at the same time. Foci are in widespread use with all known active magic users provided they use structured spellcasting.
The most prominent forms are the wand, the stick or rod and the staff. Those can be found to be made of a fast variety of materials from wood or bone to metal or almost anything else. Each material bringing some strength and weakness to the production process and the end result.
Other common but still more unusual foci include weapons, jewellery and even certain animals.

Another widely known fact about foci is that they can be "preloaded" with spells and such a "load" can be called into effect by all beings, as long as they have a bit of magic of their own. This means that almost any higher developed animal could do so.
A survey conducted by Magistra H'leria in 1245 p.fl. culminates in that "... all living things, capable of even primitive thought and an awareness of causality, have shown to be able to use prepared foci."
And the Magistra concludes - "The ability to form intend and plan action even to the small degree of a toddler, a dog even some reptiles results in the ability to use a focus. However, such a focus needs to be prepared in such a way that the subject can trigger it, which in itself makes such activation easier as the complexity of thought processes increases."

It is, however, still much disputed whether a "preloaded focus" should be classed as a regular magical artefact containing a certain magical effect.
Both, the artefact and the focus are similar yet differing. One group advocating against classing a focus in the same category as an artefact because of the difference in effect. An artefact causing a specific effect while a preloaded focus always contains a specific spell. Basically, there could be an artefact for almost any conceivable effect but a focus can only ever store a specific spell.
Furthermore, a focus does not store magical energy but an artefact does. Resulting in a certain degree of risk for people to use a focus. Non-active users can and likely will experience significant effects from nosebleeding to severe fatigue.
Magistra H'leria in the aforementioned study: "As to the repercussions, we have seen a cat losing its hair on half its body and another one being not effected at all."
Obviously foci and artefacts have been and still are the topic of many an essay by scholars all over.

Transsciption of a scroll found in a ruined city on the subcontinent of Varleria. Obviously a homework by an unknown Apprentice, dated back before The Wave for obvious reasons.

"Wands and staves are all purpose tools, the main difference it a wand is powered by the users own magic.
A stave is powered by the ambient magic all around us. A stave is an order of magnitude more powerful. If a wand is like a bow, a stave is like a ballista. While not useful in a close fight 'cause it limits the user's mobility, it is magic's only long range weapon and if its owner can learn to control it, it can be quite powerful.
A stave can break any spell cast by a wand and no wand can break a spell cast by a stave, not easily. A stave user can erect powerful and nearly impenetrable wards and break curses no wand user could hope to break. And this is without regard to the power of the wizard with the stave.
That's why they're illegal here. You can own one. You just cannot buy one or sell one."