The legendary damage for your attack is a good choice as the frontlines are for most slow moving and thus you can deal insane damage while counter their damage with you illusions (you can also use them to disrupt the beam of torvald)
Force Torvald to use his Recharge ability in order to maximize the effectiveness of your Energy Shield. Don't pull it out before he uses that ability. It will recharge his shield faster and your shield will be severely crippled.
Make sure you pickup Totemic Ward which gives CC immunity to anyone in your healing totem range. This can cripple a Torvald's Ultimate. Also great load against other CC champs like Cassie, BK, Tyra, and Pip Evil Mojo(Chickens).
You should put a mine at your current position or at a point where you know he MUST come around. As you hear your mine you have 2 choices: 1.you kill him 2.you use your teleport to get away I would recommend to teleport to/near your team.