Are you trying to escape?!

the standard logic of arachne is useign the 3° hitting the enemy for create a path where you have increase movement of 40% and the enemy have decrease movement of 40%. the 4° skill work similar creating an area of 25ft where you are faster by 40%.
After that you use your 2° for lock the enemy and you 1° for make seriouse damage and heal yourself

the core items follow the logic of increase the potential of the 1° and 2° spell: the warrior starting item garants a good survivability during the first minutes (if you are in conquest, is better take assassin bless) and warrior tabi garants a good amount of power. hastened katana make easier land hits on the enemy and for this reason the 2° work better, hydra's lament empower the damage form the 1° and the 2°. The basic pattern for engage a fight is the follow: 3°-hit-2°hit-1°-hit. if this work, you could have a enemy with half life and rooted; your passive will finish the job.

if you want engage with your ulti, arondight and shield of regrowth will garants you a good combo of damage and survivability.

your job is enter in the fight form behind kill the mage or the dps and run out, your teammates will do the rest