Couple of things that make this less horrible.
The int of 20 at start becomes an int of 28 by level 28, which is +9, rather than +8.
The Atropal has a 42 AC, 42 fort, 37 ref, and 40 will.
With a +29 to hit, your character has a 50% chance to hit will(11+). Ref is a 65% chance to hit(8+), fort...