The standard Trump Deck includes a version of the shadow Earth tarot deck, with the family Trumps in addition to the cards of the tarot. However, the standard Trump deck does not include Trumps of long-dead Amberites (such as Osric and Finndo). Depending on when they were drawn, standard Trump decks may or may not include Trumps of recently dead Amberites (such as Brand, Deirdre and Eric) - ones from before Patternfall do; ones from after it do not.
Personal Trump Decks can be brought by anyone who can justify it. However, Trump decks cannot be found in Shadow. Note that extra Trumps and the like will become part of a deck (for purposes of finding it in shadow if lost) if added to it, and stop being part of it if they are given away.
Although Trumps can only be drawn by those with Pattern or Logrus who have been so trained, they can be used by anyone. However average shadowites don't have enough Psyche or Endurance to initiate a Trump contact over much more than a few miles in the same shadow.
Trumps are harder to use in (and to or from) Amber and Chaos than out in shadow. They can be used (with some effort) to contact people who are within or close to any of the Patterns, but Trumps of the Patterns themselves or their immediate surroundings can be drawn, but simply do not work. It is entirely possible (with some effort) to Trump out from by or within a Pattern.
Trumps are not indestructible, though they are easily tough enough to resist the effects of normal day-to-day abuse. If someone wants to destroy a Trump, then they can.
Trumps do not go warm if their subject is killed or destroyed; they just stop working, but still go cold when concentrated upon.
Group Trumping of someone is good for getting through barriers, across distance, and the like, but not for psychic attacks; in any case the Psyches in the group add to the highest in a non-linear fashion.
It is possible to physically attack someone through a Trump link. This must be done using weapons which are in physical contact with a person who is in the Trump link - projectiles 'fall out of' the link and have no effect (apart from on anything behind the Trump image). However, unless the target of this attack is held in some fashion (or mind-locked), or the attacker has a very large Warfare advantage, then the target will be able to break the Trump link before more than one or two blows have been made.
It is possible to find shadows in which a person cannot be Trumped (Trump-barred shadows). These come in two varieties. First, there are shadows inside which Trumps simply do not work, either from place to place inside the shadow, or to or from inside the shadow to locations outside the shadow. That is, the entire structure of the shadow prevents Trump from working. Secondly, there are shadows in which the 'anti-Trump' property is confined to the shadow veil around it only. That is, shadows in which one can Trump without problem from place to place within the shadow, but cannot Trump into or out of the shadow.
There are also shadows which are harder to Trump to, to varying degrees, rather than entirely inaccessible. These are considerably less use than entirely Trump-barred shadows, but they do exist, and in the form of both shadows all of which are harder to Trump to, or with shadow veils which are harder to Trump through.
Shadows which are harder or impossible to Trump to come in two varieties (which can be of the 'entire shadow' or 'veil only' type). First, there are single isolated shadows which are harder or impossible to Trump to, simply due to some local convergence of shadow properties. Secondly, there are areas of shadow in which it is harder to use Trump. These usually start with shadows which are slightly harder to Trump to, with the difficulty of Trumping increasing as one goes into the area, then dying away again as one leaves it. In some of these Trump-resistant areas of shadow the shadow or shadows at the very centre of the Trump-Resistant areas are entirely impossible to Trump to or from.