So take for example the Hill Giant, a CR 5 often considered "underperforming" for their CR. While the Hill Giant can in theory do a lot of damage in O5e, it tends to be easily disposed of.

But now, an average crit from a Hill Giant Club does 37 damage. A 5th level character has a massive death threshold of 35....and so on average a Hill giant crit will trigger a DC 15 con save or die. At worst you're paste. At best, your taking 1 fatigue and 1 strife. Now we have seen possible crit mitigators, for example there was a mechanc in the playtest to sacrifice a shield to negate a hit. You can bet players are going to consider those mechanics when such a crit comes down.... and that's an encounter no one is going to forget.

Or look at the innocent Black Pudding. Its average crit does 49 damage, enough to trigger a check for a 9th level character (and could even get a 10th-11th level with just a slightly above average roll).

So yeah single target monsters are suddenly a whole lot scarier than they were before, even if you don't take any of the new monster manual improvements. I eagerly await my deadlier overlords :)

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