Lord Zardoz
Explorer
I mean, if I throw a CR par creature at the party, I shouldn't expect to kill a PC. I should expect a fairly easy fight.
When you say 'kill a PC', are you talking about having a PC dropped to the negatives or are you talking about needing a Raise Dead or new character?
Also, I generally define a CR 'par' creature to be a legitimate threat though not overwhelming, and not necesarily an easy fight. An easy fight is one where the monster is largely ineffective and the impact on the players is marginal. A CR appropriate fight should consume some spells, either from healing or from the fight its self.
In 4th Edition terms, I expect a CR appropriate fight to use up some combination of healing surges and require most of the encounter powers.
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