Inara with Treacherous Ground will murder your whole team if you are not careful. She can trap multiple champions, allowing teammates to decimate them, and she can dish out some damage too. Consider taking Bulldozer just to destroy Warder's Field.

Found Talus' Rune? Booby trap it! That champion makes a distinctive sound when teleporting back, use it as an audio cue even when you step back from it to know when to explode your bombs.

Nearly every Barik out there has a healing card in their loadout. It provides him a heavy sustain. Cauterize is an all around counter that also works against him very well in that aspect, even without a healer on enemy team!

Viktor's Ultimate basically creates a delayed explosion in the place where you were standing, times three. But you can easily survive it with no damage to your health simply by backpedalling and bringing the shield up. It won't even be destroyed!