So bursticade has just got a huge popularity spike, and more and more people are starting to run it. Therefore, spirit of endurance has a time to shine! it halves the dmg of bursticade, and also encourages you to group up, meaning that there is less space for barricades to spawn. Endurance aura is also really strong vs auras etc. so it messes up firecases and the rest of those SP summon/aura bgs. As a bonus it beats the silly broodmother trample bg too.
Solstice Marksman has Frostburn. I wonder if we could find a way to completely negate Bursticade with Spirit of Endurance and Solstice Marksman! Edit: I tested it out. With a Solstice Marksman in play and while being in range of Spirit of Endurance, the affected champions end up losing 1 HP per relic it is near, instead of 6 HP. Frostburn heals at the end of the turn, however, and so the champion has to survive the initial blast in order to get the heal. Still, we have an answer to Bursticade, if it becomes more popular.
Unfortunately, frostburn does not stack. So if they get a full 8 barricade frosticade on 1 champ, in range on spirit, then they're stupid for not using frosticade on spirit. The champ on the other hand will still take 20dmg - 3*8 and then -4 at the end of the turn. That being said, frostburn will still mess up frosticade bgs in general because they will want to run frost amp for the combo to increase the dmg, and if they're running frost amp they will mainly deal frost dmg. But in that situation you are just running solstice for anti frost, whereas endurance aura is actually good vs lots of the decks out there atm based on how popular nontargetted DOT dmg is. You could, of course, argue that you're running solstice as a champ and just take frostburn because it will be good and ST is bullshit, but I don't think the champ is very strong personally.
Dang it, you're right. I only tested it with two relics near, instead of more, and got a bit confused. Frostburn only triggered once. Thanks for the info. I always assumed it was 4 HP per damage source. oh well.