I was playing around with the magic item crafting rules and wanted to make an interesting piece of armor. I haven't designed custom armor before.
+2 Breastplate: 4,350gp
Continuous spell effects:
Iron Body: 8x15x2,000=240,000gp
Enlarge Person(multiple different abilities):(1x15x2,000)x1.5=45,000gp
+2 Breastplate of the Iron Golem Aura strong Transmutation; CL 15th Weight 50 lbs 289,350gp
Upon donning this armor your body transforms into living iron and causes instant growth, doubling its height and multiplying its weight by 18, increasing the wearer's size category to the next larger one. If the wearer's size increases to Large he has a space of 10 feet and a natural reach of 10 feet. You gain damage reduction 15/adamantine. You are immune to blindness, critical hits, ability score damage, deafness, disease, drowning, electricity, poison, stunning, and all spells or attacks that affect your physiology or respiration, because you have no physiology or respiration while this spell is in effect. You take only half damage from acid and fire. However, you also become vulnerable to all special attacks that affect iron golems.
You gain a +6 enhancement bonus and +2 size bonus to your Strength score, but you take a –8 penalty to Dexterity as well (to a minimum Dexterity score of 1), a –1 penalty on attack rolls and AC due to its increased size, and your speed is reduced to half normal. You have an arcane spell failure chance of 35% and a –6 armor check penalty, this is cumulative with the armors regular ASF and ACP penalties. You cannot drink (and thus can't use potions) or play wind instruments. Your unarmed attack deals damage equal to a club sized for you (1d8 for Large characters), and you are considered armed when making unarmed attacks. Your increased weight while this armor is donned would cause you to sink in water like a stone. However, you could survive the lack of air at the bottom of the ocean.
Craft Magic Arms and Armor, Iron Body, Enlarge Person; Cost 144,675 gp