Those 3 life points usually didn't matter much, but occasionally they make all the difference, especially when a deck finds itself in a position to do 14 or 17 damage all at once but can't do 20
This card, on the surface, looks very similar to Lightning Boltone mana cost, deals damage
Sacrifice another artifact: Put a +1/+1 counter on Flamewar and convert it
If you are looking to cut back even more, the only card that's really replaceable is Pull from Tomorrow, which would save about $15
For the dessert I bring you a comic by Eldar Tagi-Zade and a report called I played my metagame-breaking 36 Bears in the 128-man Win a Piece of Power 9 tournament at Worlds. Mana curve is a plot that shows the distribution of cards with certain mana value among the cards in a particular deck
Im not sure how Id use Voltaic Construct in a fair build, though