Level 1 & Level 7 Echo Pulse and Particle Accelerator are the foundation of this play style.
Goal: Use your Warp Rift and positioning to improve the damage of Disruption Pulse on the return trip.
In a one-on-one situation provided you hit both rifts and the laning enemy hero your return Q does 105% damage. Best case scenario, the return trip does 125% damage. The additional burst of damage you can get on the return trip can take your enemies by surprise.

Level 4 Shield Capacitor
This is the best option since sometimes you may have to position aggressively to take advantage of Echo Pulse and Particle Accelerator.

Level 10 Null Gate
This is really valuable in choke point areas in maps otherwise use liberally against enemies as CC or to help guarantee a secured kill or a last-hit return Pulse kill.

Level 13 Aggressive Matrix , Power Overflowing (optional)
If you have several mages power is a good option, otherwise pick matrix for the increase to attack damage to all ally Heroes.

Level 16 Quantum Entanglement
The more often your opponent is slowed the easier it will be to guarantee return particle-accelerated pulses. Repulsor makes your return hits trickier but it might be an important option to interrupt dive tactics. Also, consider picking up interference to deal with enemy mages.

Level 20 Probius Loop, Gate Keeper
Both talent choices are best when your team can keep the enemies CC'd or clumped together. Loop works very well with Echo Pulse and Particle Accelerator and is generally going to be more useful. However, in maps with more choke points you can get really good zoning value with Keeper.