Bless at low-to-mid levels and spirit guardians later are the best things Shadowheart can spend her concentration on for, like, 95% of situations. Both spells are extremely good, just like they are in the tabletop. Never understood people criticizing Shadowheart for being useless; she’s a Cleric, and that’s great already even if her subclass (which you can respec her out of) is subpar for the class.

She was so slow for most of the game that I couldn't make much use of those. Near the end she got some boots that gave her freedom of movement, and longstrider, and then I started doing the same thing with her. Just using dash and running over next to everyone. LOL

Edit: it was the courtyard right before you start climbing to get to the brain. I dropped an ice storm on top of the group with the spectator, and that was pretty satisfying. It killed everything except for the spectator. Is that the courtyard you're talking about? My favorite playing with fire moment was a fire bolt in the sewers on all of those grease monsters. Half the sewer went up in flames!

Yesss I stumbled across this in act 2, and basically fell in love with the character growth that seemed to happen at the same time.

This isn't a flex or anything but I've played through 3 full campaigns and I just realized I've never cast fireball...what is wrong with me...

I always use her first bonus action after casting Spirit Guardians to cast Spirit Weapon. If nothing else, Spirit Weapon is great to distract enemies into attacking it rather than our party.