Force and glimmer are good defensive items, but so is aether, and it also acts as offensive, therefore top choice. Medallion is the best early game item, as it allows venge to help nullify enemies more effectively and gives much needed mana regen. Beyond movement speed, medallion for murder, and aether as both the best defensive and offensive item, everything else is situational. Though force is highest pick, as it is the cheapest option to break linkens, the nullifier of swap.
Magic missile is best burst skill early game and best disable venge has beyond ult. Play around this fact. However, mid game, best burst is allies. Play around this, too.