With your shield, your ult, challenging smite, I find that you can 1v1 pretty good on Ivern.
I went 12-7-16 in a game today rushed devourer > wits > swifties > nashors > sunfire > GA
Felt pretty strong actually, some of the kills where clean up kills but I actually did a lot of work myself too.
I have a nice clip of me going in 3/4 life and getting caught out solo by Katarina and beat her down with only devourer + negatron (had red buff too), I ate her full channel ulti + combo and chipped her down in a few seconds even though she was doing good.
I find team fighting on Ivern to be pretty fucking hard, and many fights if I do survive I really have no idea why, must be the hiding in bushes not sure.