I always try to make it a point to review cards that I initially think are pretty lame, and turn out to be a diamond in the rough after playing with them extensively, and Livery of the Tower is most certainly one of these.
The instant you see this card, the initial reaction should be to compare it to Blood of Númenor; it's same cost, same sphere equivalent. At first glance it appears much weaker, as it is unfortunately restricted, "more" restrictive on the type of heroes it can be played on, it's effects are only relevant for a single attack vs. the entire combat phase, and it makes any boost >1 more expensive. Indeed on most defensive characters, it probably isn't as good as Blood and I initially included 1x in my Beregond deck as a "2nd rate blood" option just to have 4x boosting options.
However, what I learned is that on Beregond (whom it's obviously designed to play on), there is a case to be made that it's actually a really good card that can outperform Blood in the right circumstances. To illustrate this, I need to do a little bit of math.
So Beregond already starts out at a hearty 4 , and let's be realistic, if you are playing Spirit Beregond you are probably auto-including 3x Arwen Undómiel for both compensatory and extra boost for a strong defensive sentinel character in sphere. That means in most games Beregond should be defending at 5. What this means is that for any single up to 6 (5 without Arwen), Livery is effectively mostly equivalent to Blood in boosting. However, it has an ADDED benefit of also being able to cancel any form of direct damage, whether it be from enemy ability or shadow effect. This also guarantees that you will trigger Beregond's reduction from this defense (since the way I read his ability, a shadow effect that does direct damage counts as "damage during an attack" and thus negates his ability). Blood does not stop direct damage. As enemy increases to 7+ (6+ without Arwen), the defensive boost on Livery gets marginally more expensive.
So which is better? Well that depends on the Circumstances. I'll look at each dynamic that impacts the decision numerically:
Multiple enemy s at the defender's +1 or s at defenders +2 or greater make Blood a more attractive option, with it's attractiveness increasing with number or magnitude of enemy attacks. This also means that Blood is more likely to be a better option at lower while Livery becomes a more attractive option when is higher. For most decks on most heroes, Blood is going to tend to be better.... but one can argue in a properly built and played Beregond deck, by the time that you are facing multiple enemies with giant s in most decks, you are typically already in late game and should have a mountain of resources on him where the extra potential cost of Livery matters less.
Quests with more direct damage very obviously favor livery, since it does protect against it whether it comes in the from of shadow effect or treachery. As mentioned earlier, cancelling direct damage shadow effects might allow Beregond to trigger his threat reduction in a circumstance where he otherwise might not have. More direct damage in a quest makes Livery much more valuable.
Blood is applicable to a wider range of defensive heroes, so it does have that going for it although that is a deckbuilding problem and not a gameplay one.
The biggest dig against Livery in my opinion is that it is restricted. This is a detriment because it discourages attachment stacking on big defensive heroes. However, once again this is less of a problem for spirit Beregond than it is for defenders of other spheres, as most of the defensive attachments in Spirit are not also restricted. It's a much bigger problem for Tactics Beregond who tends to want to accumulate other restricted attachments.
- Lastly, it's important to note that even in a deck/quest combination where you deem Blood to be the better option, Livery can still function as a 4x-6x "2nd rate" Blood in order to better concentrate the deck and increase the chances of a 0 cost defensive option in the opening hand.
In summary, Blood is a much easier played and generally powerful card overall, but Livery outshines Blood in certain builds, quests, and circumstances. Whichever one you deem to be a better option for your situation, the other can function as a less ideal substitute as well.