D&D 5E (2014) Your CR limit for an average 1st level party?

[Mull Ponders]

I tend to look at it a bit differently. An Orc with a great axe is 1/2 CR, but can down a party member with a single shot. A Carrion Crawler is CR 2, has a ton more HP, but is going to paralyze a party member and drag it back to it's lair to be eaten later, allowing a rescue. I look at possible outcomes more than CR ratings.

 

[Zardnaar]

CR 2 or 3 is pushing it. Accuracy isnt great and a crut can outright kill a OC with a ok to decent roll vs max damage or close to it.

Depends on monster as well.

 

[Koloth]

Be very careful with any critter that do AOE things like spells, breath weapons or similar. A 4 v 1 can become a 2 v 1, or worse, very fast once AOEs start going off.

 

[Zardnaar]

Be very careful with any critter that do AOE things like spells, breath weapons or similar. A 4 v 1 can become a 2 v 1, or worse, very fast once AOEs start going off.

Hell hounds 7d6 breath weapon iirc.

 

[Jeremy E Grenemyer]

My instinct says CR3 but I wonder if I am being too pessimistic...

My instinct is the same as yours.

You mentioned not downplaying the monster, which I think is important. Players sense when DMs are flubbing dice rolls and "bending" the game reality to fit a narrative. That's not terribly fun.

However, something I learned back in 3E is that it's possible to use monsters with much higher CRs than the average party level provided you significantly pair the monster down in power and have the reason for that pairing down be linked to the encounter environment or a larger plot element in the adventure/campaign arc.

For example, having a Glabrezu stuck/merged into the wall and floor of a failed summoning circle makes for an interesting dungeon room encounter. Maybe only its head, upper torso and fists are free to use; everything else is in the wall/stuck between realities. Does the Glabrezu attack and eat whatever wanders in? Does it try and make a deal if it encounters a spellcaster---especially a low level caster that could be taught how to cast more powerful magic in time? Would the creature's predicament by a puzzle that one or more PCs might want to solve?

I know this is beyond what you asked. Your inquiry just reminded me of some of the things I've done in past games to keep my players on their toes.

 

[UngeheuerLich]

Level 1 characters are a bit more durable in 5.5 on average.
CR3 still seems dangerous. A quick search tells me that they deal 11 to 17 damage on average on a hit. Enough to down every non-martial/half-caster at least. And they have abilities to either increase that damage, do area damage or disable the PCs.

So my guess is that PCs should be able to handle it if they can chose how to fight but only with luck, if the CR3 creature more or less surprises them.

Chances for PCs to win increase dramatically if the spellcasters can hit them with disable like command or tasha's laughter or sleep.