Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Pros / Cons
+Tons of AS=Tons of AAs=Tons of W procs=Tons of damage.
+You can 1v1 pretty much anyone, and if you play it correctly and your team peels for you then you can probably get an easy penta.
+It's generally a very fun to play build and I prefer it on other ADCs too, though I think Varus is probably the best ADC for this kind of gameplay.
+100% crit :^)
-If you don't have a GA, and the enemies have way too much burst, then you're probably screwed.
-You need to kite well since you have 0 escapes, and it is highly important you have a decent laning phase, since the items are quite expensive and it is easy to fall behind.
I think the best supports for Varus in general are tanky supports with hard cc as initiations(Alistar, Leona and so on).
You have to farm very well and be very careful not to be in a bad position since you can easily get caught out as Varus, since you have 0 escapes. This build is generally quite expensive but if you manage to pull it off in time then you'll be and absolute monster and dominate completely everyone you're up against.