What are everyone's thoughts on the 'mantra' line of skills? The Watcher's enlightened form is crazy (3x damage, no penalty when taking damage) but most of the cards that give mantra don't actually do anything that affects the board.
I find Pray to be decent - enough mantra that you might actually trigger it during a hallway fight, while the insights it generates guarantee that you'll have plenty of attacks to play when you trigger the form. Worship, on the other hand, just doesn't seem worthwhile - sure, you only need two for the trigger, but it costs an unupgradeable two energy. Prostrate is free and gives (a little) block, but needing 4 or 5 pretty much assures that you'll never get the trigger in hallway fights.
Haven't played around with Blasphemy yet - definitely a card you want to triple-check your damage numbers before you play, and avoid anything that auto-plays your cards.
A devotion (the 1 energy power that gives 2/turn, 3/turn upgraded) and one or more prostrates (0 cost, 4 block and 2 mantra, 3 upgraded) makes it worth using. Adding in the relic is nice as well. Especially with brilliance. All of my successful decks have been devotion decks or establishment decks with a lot of luck.
I only ever had one of the Worship cards, because of a Neow transform. I even used it once because the enemy wasn't attacking, and I only had that and blocks. It's not a good card unless you're planning on having bad draws or a lot of extra energy (which, being the watcher, isn't entirely unreasonable).
What are your thoughts on those "synergy" ( does x if last card was Y) cards? I've made limited use of those, mostly the "crush joint" (apply vulnerable), but I'm not sure if it's worth it to try to set them up.
Crush joints is the easiest to set up, because you start with a miracle. Wrath, miracle, crush joints, then 2 attacks is a nice opener. Also, agree with Sindain that any debuff needs to be upgraded to a second round to be good.
As I ascend, the issue I've had with Watcher is 2nd or 3rd act enemies that scale (and, depending on card draws, Nob). If you don't have a source of calm or an Empty Body coming next draw, popping Wrath to take them down quickly is a huge gamble. Not doing that means you don't take them out before they outstrip your ability to attack/defend. Watcher really doesn't have much that scales.
Also, I'd like a Neow option to add one basic character-specific card to your deck (or trade out a strike/block for one). Empty Body would be a great additional starter for Watcher, maybe ball lighting or cold snap for Defect, backflip for silent, and probably iron wave for ironclad (I'd say bodyslam, but that's not as build-agnostic as I'd like). Not something that would define your build, but something that's useful for most builds that interface at all with the thing your character does (watcher has stances, defect has orbs, etc.).