First up, the Skulk.
The key points to take away are:
- Stay away from the floors. Run along walls and ceilings to make yourself harder to track.
- Use your Parasite ability often, but be careful to to have it selected when you want to do damage.
- Watch for leap research, it will make you much more effective. Give commanders the benefit of the doubt when leap research is slow - they may be prioritising an alternative tech path.