Will be posted once everything in my head is on paper and at least somewhat organized. 
Basics: Forged in the last few years of the Last War, Bastion did not see much action during his service. Once it was seen that he had a lot of potential in regards to crafting, he was taken in by an Artificer by the name of [NAME_UNKNOWN]. While he was skilled in the creation of Armor, and to some extent Minor magic items, he was often distracted, longing to see the action he was promised but never given. One day, as he was pounding away on one of the few armor orders they had taken recently, his mind began to wander, dreaming of the honor and glory that could have been his. Before long, he realized that he was being scolded, for he had absentmindedly hammered a hole through the Breastplate, and the entire order, which had taken weeks up to this point, would have to be re-worked. 
"This is the final straw, Bastion. You're a good worker, and I enjoy watching you mess with your sciencey who-za-whatzits, but Ye're too dang oblivious. I've put up with it til now, but it's jus' too much. This is the fourth set this month that I've had to do over because you're too busy thinking of the war. "
Bastion proceeded to pack up his belongings, and he did the next best thing to fighting in the war. He signed on with a group of adventurers.