synergetic upgrade for Escort Service ability

[DreadKnight]

Scavenger's Escort Service upgraded should do something else that being able to move large units, as it doesn't add too much to the table if playing Envy only, since Night Stalker is the only large unit over there.

Perhaps it could be usable indefinitely, as that would allow moving around more units. Or even better, it could allow moving units to different rows as well, as this could create really good synergy with Night Stalker's Screaming Bat ability.

[DreadKnight]

Or it could start out with being able to move sideways (replacing inline with nearby location) and when upgraded it could be usable indefinitely.