I've played Vorazun the most (Lvl 8). DT's and Blink Stalkers FTW!
Have tried all the character up to at least level 3.
If I were to rank them for strength in the early-mid levels i'd go:
Vorazun
Swann
Raynor
Kerrigan
Artanis
Zagara
Zagara's limited supply and weak units don't really interest me. Plus zerg can't really expand in co-op, as they would normally in other formats.
Zagara is pretty much only one I've played, at lv 13 atm. Her strength is in how cheap her exploding units are (banes and scourge). Banes get spawned for free periodically at baneling nest and the scourge cost almost nothing once you have the hive upgrade. Abberations spawn 2 banes when they die, and at lv 14 banes split into more banes. All you have to do is A-move into enemy units andd they explode. You get scourge ups at lv 4 and the free banes at lv 7. Abberation death banes are lv 8.
While you cant expand infinitely, you can expand the fastest out of all the current heroes. First thing I do is make a pool, no drones. Make a large round of lings, kill the rocks and expand before making a queen. Once you have lv 12 and swarmlings, you can take the natural at 2:10, which is insaneeeeeely early for co op. You can also saturate the fastest due to double drone production.
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