What follows is a breakdown of our reasoning behind recent balance changes in the StarCraft II: Heart of the Swarm beta.
Void Ray
We haven't seen many players microing against the Void Ray's Prismatic Alignment ability, even among the highest rated players in the HotS Beta. In order to encourage more precise micro against this ability, we've decided to display a timer on the Void Ray for the duration of the effect. We're hoping to see players pull their units back against Prismatic Alignment, and re-engage once the ability is on cooldown.
We also felt that Void Rays were too strong in the late game for their supply cost, so we decided to increase this requirement by 1.
Reaper
We think that Reapers are headed in the right direction. Players are really forced to utilize the Reaper’s passive healing ability between attacks in order to maximize the unit’s efficiency. We'd like to further promote this type of play by slightly increasing Reaper health.
Burrow
We decided to move the Burrow upgrade requirement to the Hatchery, because we feel that early Burrow usage with units like Zerglings, Banelings, and Roaches creates potential for more action during the early game. Furthermore, the initial feedback from players has been very positive regarding this change, and we've already seen Zerg internal testers pull off some neat tricks using Burrow.
As always, thank you very much for your input. Please take time to playtest these changes before providing us with more feedback.