Shadowverse

It’s enough to either take him out with a “Necromancer” or kill him with a “Death Knight” in the same turn.

Not a very rational way, and it also depends on luck.
No, I agree that most factions, if they have healers, can often apply something else to them in parallel, but forest creatures don’t have any additional effects (except for controlling the board). But still, from the point of view of a pure healer, I can’t see the Sylvan faction as an underdog...