You can see why they're rare as they can give a player a somewhat unfair advantage if they have been building up their fighting prowess as opposed to the player who has been working on their mastery game.
Opportunity, because the player who defeats them (and a player needs to be dishing out at least ten damage to do this) will receive a hefty bonus, be it a chunk of mastery, a free Destiny or a second relic. Calamity, because if they make it to the end of the revealing player's turn, they will take life, cards, Mastery, or a combination of the three. Now, there are not that many of them but when they do appear they bring both calamity and opportunity. Enter The Ingenimex - Evil (Or Eviler) Versions Of The Five Shard Masters In Shadow of Salvation, we saw big bosses and their minions appear to do battle with your fragile alliance of Shard Masters, but they weren't to be used in the PvP. Shards owe a lot to this franchise for its existence, but the one thing that it didn't have was something in the deck to beat up due to a lack of victory points to gain. Now the game that really put the two Garys on the map was Ascension, undeniably, and a good measure of what two individuals annoyed with TCGs can do when they put their mind to it. Love, Sets, Ingenimex - Coming On Like A Seventh Sense What it does mean is that playing the same people is going to get shaken up as Destinies change. Hey, it's a super-boy and dog eat super-boy and dog world. Then this might all be upset when someone goes for the same card, they've set their heart on. Another might give them extra firepower if they play low-cost Heroes, meaning that they'll pick up the cheap cards. One might allow them to increase their Mastery if they play four different factions' Heroes, so they might go for a mix and match approach in picking up cards. There are six available at the beginning of the game, which means that from the start players can begin to plan their strategies around getting these Destinies. Most of them can be 'exhausted' like Champions for a per turn effect, some of them have an instant one-time effect, but all of them have the stipulation that a player can only have one Destiny. There are 30 possible Destinies in the expansion, all with different effects but all obtainable once a player reaches 5 Mastery. This brings me neatly via this 'bring you up to speed' side-track to Destinies.
You also had the option to customize your starter deck with better cards for the co-op mode, though there was nothing to stop you from adding a bit of 'spice' to your PVP game. This also added a completely new faction, Aion, who introduced the ability to fast-play any hero, an option previously only available with Mercenary cards. Following on from Relics came Shadows of Salvation, which did not add much to the mechanics of the game but did add the opportunity to play co-operatively and included one super-boy and his dog(s), Rez. A tricky decision to make, but one that could have game-winning consequences. The only problem was that you had two to choose from and you could only choose one. So along came Relics of the Future, which introduced Relics, super-powerful cards that could be put into your hand when you reached 10 Mastery, and which powered up again at 20 Mastery. This meant that playing the long game of gaining Mastery to max out your Shard came with the very serious risk of being dog-piled long before this happened. Time was when Mastery only served to power up a handful of cards, including the game-ending Infinity Shard.
ITH has some game-changing elements that will make even the most set-in-their-ways strategist reconsider their play… Ko Syn Wu, Can You Handle This? I Don't Think You Can Handle This… Unlike Shadows of Salvation, Into The Horizon is a small box expansion, but do not be fooled by its diminutive size. Hope, after all, is the thing with feathers. So, I will consider this a swansong and hope for a reunion by popular demand.
The only problem is I can't remember if it's three expansions or four. This is because the two Garys have already set a limit on how many expansions there are going to be. Much as I love seeing new expansions for Shards of Infinity, each one brings with it a tinge of sadness.