
Always try to flank and hit the squishies with this build. Use your 2 and cait away if they invest too many resources on you. Try to delay your ultimate as much as you can.
Sphere of negation is a strong replacement if they are magical heavy (such as Alladin jungle, magical mid and support)
I would only swap mantle for breasplate in case they are very heavy on physicals (4 or more) - in which case you may want breasplate on the 3rd/4th slot. Any later than that, its value is reduced.