My son has a hybrid Wilden Shaman|Runepriest and his AC is awful. How can I get it higher?
He's taken no feats related to AC/defense and is level 4. Rebuilds are possible.
Take the Hybrid Talent feat with the Runepriest Armor Proficiency option.
This gives him scale armor (up from leather) and light shields. This should get him up to a 21 ac or thereabouts. A gain of +6 over his likely current AC for one feat can't be beat.
10 + scale armor (+7) + light shield (+1) + 4th level (+2) + magical armor (+1) = 21
If he is lacking magic armor, a 20 is still respectable.
Some typical 4th level opponents and their attacks:
By the "book" everything should have Level+5 to their AC attack and a 20-21 would be a very reasonable defense against that.