So I'm going to do something a bit different: I'm going to pick a few classic monsters from both the MV and Pathdinder's Bestiary and run a comparison.
Before I begin I do have one thing to say about the MV: I miss a few monsters in it. It lacks most good-aligned monsters (there are no metallic dragons for example, but there are elves, humans, dwarves etc.), but that makes sense. It's a book of monsters, not an encyclopedia of flora and fauna in the world. It's not really a complaint. It also lacks any semblance of aquatic monsters: no kuo-toa, no saughin, no merfolk, no dragon turtles, no aboleths, no krakens...it does have a shark, which makes it weird, because I have no monster to pair them off with. This isn't a big deal but it's a bit sucky (especially since I'm a big fan of the ol' fishfolk). It also lacks any kind of elementals that aren't of the lesser type. Now this I find just plain weird. You include four elementals, even specify that they're lesser, but don't include any medium or greater or whatever? Now that's just bad-weird. Thankfully there are some Archons, which are a kind of elemental angel-demons, serving the Primordials, which might double as a higher-level elemental in a pinch. The above omissions (greater elementals, fish folk) become even more jarring when you realize the book has three different monster entries for Ropers. I mean, really, Ropers? They were one of the stupidest monsters even back in the 3.0 Monster Manual and here they get three types? The Roper takes up four pages! Likewise, stirges get four different entries. This is by far the book's biggest flaw. I'd gladly exchange a page of stirges (do we really need that many different kinds?) and the four pages of ropers for a few fishmen and more elementals or something. One last minor nitpick: there's a goblin beast-rider type but the book isn't exactly clear on what kind of mount he's supposed to have and the only ones in the book that seem appropriate are several levels higher. Still, nothing that shifting a couple of numbers around wouldn't fix.
With that critique out of the way, let's move on to our first classic monster: the goblin.
The Bestiary offers us the baseline creature: a Goblin, worth 175 XP, 1/3 Challenge Rating. The Moster Vault doesn't have "vanilla" racial creatures so the closes thing is the Goblin Sniper, a level 1 minion artillery, worth 25XP. Now, the 1/3 CR in Pathfinder means you need 3 of these fellas to present a lvl 1 challenge, whereas the Minion type in MV means you need four of them to count as one lvl 1 challenge monster. That lines up pretty nicely. The MV creature is seemingly worth a lot less XP but you have to consider the 4E encounter XP budget which means that 4 minions don't really constitute an encounter by themselves.
Next on, the Bestiary gives us the Alignment, creature type, Initiative and, senses/Perception. MV pushes Alignment all the way down to the bottom - the Goblin is CE, while GS is (4E's equivalent) plain Evil. They're both small humanoids, but the GS also has the "natural" type, to indicate it's not a magical creature. Redundant, but still.
The Goblin's Initiative is +6 while the GS only has a +3 bonus. The Goblin has darkvision and -1 perception while the Sniper has low-light vision and +1 perception. Slower to act but more perceptive.
The Goblin has an AC of 16 (+2 armor, +2 shield, +1 dex, +1 size), while the sniper has a mere 13. The strange thing here is that it has a +3 dex and wears leather armour, so technically that should be at least 15 (size doesn't give modifiers). I guess the lower defence is part of minion math, possibly maybe.
So far, so same-y. The big difference comes with HP. The Goblin has a mere 6 HP, while the Sniper, being a minion, has only 1 HP. Technically, that makes them more or less the same (since the average lvl 1 fighter with a sword should be dealing out at least 6 dmg per hit. However, a non-minion lvl 1 goblin has a whooping 29 HP. This is part of 4E's low-level HP buffering which makes lvl 1 characters (and monsters) less fragile (at higher levels, this difference from PF to 4E is reversed).
The Goblin's saves are +3, +2 and +1, while the Sniper's defenses are 12, 14, 12. If we used the static defense house rule with PF, those saves would be 15, 14, 15, so definitely a few points higher. Because of different math, if you want to translate the 4E goblin into PF you'd need to subtract roughly 10 from the defenses to get his saves. I wonder if this will hold with monsters I will review later.
Both have a speed of 30ft. or 6 squares. From there we go to offense. Both attack with a short sword and a shortbow, but the Goblin's attacks are +2 and +4 respectively, while the Sniper attacks with a +8 on both melee and ranged. That's a huge difference. While I expect this to even out with higher levels (PF having a more exponential progression, 4E more linear), it's still a big change. It also shows how monsters in 4E don't really follow the same rules as PCs, since the Sniper's +1 str and +3 dex don't seem to influence the melee and ranged attacks in any way. Interestingly enough, the other two lvl 1, non-minion goblins in MV have an attack of +6. Which strikes me as odd. The Goblin does 1d4 damage, but has a high critical (19-20 with short sword, x3 with shortbow, while the minion just does 4 damage, plain and simple (and 4E criticals just deal maximum damage). The non-minion 4E goblins deal something like 1d6+5 dmg on a hit, which is four times what a PF goblin does on average, but this factors into the much higher HP count.
And that's pretty much it for the Pathfinder Goblin. Their statlines are very similar (the PF goblin is smarter but less wise, while the 4E is slightly stronger, stupider and wiser). I'm going to skip skills. The PF Goblin has the Fast trait, which means it retains the 30ft. speed even if it's a small creature. The 4E goblin doesn't need that, for two reasons 1. the old size rules aren't there anymore 2. monsters don't follow the PC rules in the first place, their speed is whatever it needs to be instead of some required base which is then modified by traits.
The 4E Goblin has one additional shtick, which is Goblin Tactics. Every time it is missed by a melee attack it can shift 1 square (5ft step) for free as an immediate reaction. These little tricks are really what makes 4E monsters unique and interesting. The question here is how these special moves that 4E monsters have (like Goblin Tactics) would influence play if ported into PF. Would they break the game? Make the monster too powerful, despite the numbers being balanced? The only was is to play and see.
So far so good. To keep it really loose and simple it seems that if we want to port lvl 1 4E creatures into Pathfinder we need to:
-lower their HP down to 1/4, unless they're minions
-subtract 10 from their defenses to get their saves
-shave off about half of their attack bonus, possibly more like 2/3
-shave their damage down to1/4 (in line with the lower HP)
Or vice-versa of course.
That seems very easy. In my next posts I'll take a look at a few monsters with higher levels and see how (and if) that math holds up across the board. The real trick here isn't math however, but the 4e monsters' powers - from a conversion point of view: are they just encapsulated maneuvers that PF monsters could do anyway (and optimize for with a level and a couple of feats) or is it more weird than that?