243a0200_ne_Arena_Strategy___Blue_is_Me__Advantages
[Name] Crackling [Disadvantages] Weak against. Devil dogs, Warp Zealot, air units. [Advantages] 
Really fast movement and attack speed. Can burrow. Fast spawn rate. Good against Marines, slow attacking units, and armored units. Upgrade armor, health and weapon equally and they can be hard to stop. Can increase attack speed to 0.29 from center mercenary shop.
Starcraft 2: Marine Arena Strategy | Blue is Me
Advantages