How do you play as sentinel?

[Challenge your mental]

All the other characters feel good but this one is plain trash, its a boring slog trying to keep this weaking alive as it can't seem to kill anything fast enough.

[Silent]

Yeap, sentinel is not the fastest killing machine but he still pretty good.
Stack armour for yourself, boost your barriers, destroy enemies armour.

[bob.bfan]

Wow, sentinel is my fav character. Utilizing cards that cost very little and allow you to drop arrow after arrow work really well on him, combine this with the common rune that gives you %dmg per card played really helps boost DMG. I've found that the "multishot" cards arent as clutch on him, since if you draw a smoke arrow and hit the wrong target it can really mess you up with the armor the enemy gets. Surprisingly, I don't use the ultimate ability that often. i go for specific quivers based on my runes and abilities. Anyway, here's a light guide I found that might help you out
https://gamerant.com/tainted-grail-conquest-best-sentinel-build-guide-tips-tricks/

good luck :D