I bet your talking about Vanguard here. He's a pretty tough champ indeed. But SL bonus only applies to dmg dealt by champs, so make use of Boomerang and focus fire. If you have at least 5 champs out it will give him easy target. Work from there to create an advantage. Champs like hook fiend or Minotaur Cullers can help you setting up the kills. Try your best not to leave any SL champ at low HP. They can easily heal back or deploy that reinforce champ.
I don't know, you said I need 5 champs on board before I can face a single SL unit. I can understand Culler cause he have strike, but I don't get the utility of Hook Fiend.
You don't need 5 champs to face one, never said that... Dragging Attack and Grappling Hook are good for setting up kills.
