That first one is knight class i believe, i have silver one and they share same skill. What their skill do is boost their atk&def at every specific set of time (should look at wiki for reuse and initial timers) also have a rather short ranged attack which is not bad along with decent hp,def,atk.

That ranger needs to be definitely prioritized over bashira because of her utilities along with a decent rate of assassination chance.

Lastly i have that gold heavy cannoneer dude too, he's very good at goblin clearing for me now and have primise for G crystal map but that needs his aw i think. Also i find his skill very good, can acts as an off-tank pretty good with his splash attack along with mediocre def at skill use.

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Knight's stat increase is permanent i think, cuz it has a veeery long cooldown ;/ i'd focus nearly anything i got from shrine anyway at plat+
Some gold ones like that dude and rino are also good to have.