Based on the articles WotC has published already, it seems they have a good idea of the general feedback. So I'll limit my better-late-than-never playtest to a few key topics. We only played at level 1.
- The wizard went over badly. While I initially thought HP were too low overall (more on that later), in practice the only character with durability problems was the wizard. Also, the fact that his big daily attack was Burning Hands was actually a problem: he didn't want to waste it on kobolds or centipedes (rightly so), and it's not helpful against one big target. Other than using Comprehend Languages to good effect (I had the pechs discuss the adventurers among themselves in Terran, so listening in gave the players clues about how to placate them), all he did all day was Magic Missile. He was bored the whole time, except while the gelatinous cube was eating him.
- Defenses are adequate but swingy. The high ACs and low enemy attack bonuses meant that the party was sturdy enough (except for the wizard, who had roughly a 33% chance of going down any time I said I was attacking him), but a couple of unlucky rolls will mean disaster fast. More HP and better enemy accuracy makes for more consistent fights (which might also be considered more boring...).
- The cleric found himself in the age-old position of having to choose between fun spells and healing. As a result, he had no more fun than the wizard, and only got to cast Lance of Faith all day. Also the healing, while limited, was super-powerful at this level, and almost always over-healed.
- The fighters had fun. No complaints there.
- The rogue was an odd case. No need to hide to get off sneak attack, because none of the monsters were tough enough to merit it. But her skill reliability was a problem for me as the DM, because she never failed at anything. Can Find Traps be used passively? I don't want my players to have to go back to the 1e/2e adventuring style of searching everything every step in a dungeon they take, but if it can be used without explicitly stating so, it's basically trap immunity, with a thief-rogue in the party, unless the DC's are high enough. Since monsters had garbage skills (no trained skills, no Wis, no Dex--even the kobolds had only +1 Sneak, and nothing had above +0 Spot/Listen), the PCs always won. Except for the gelatinous cube, with its blindsight.
- The adventure sucked horribly. They did chapters 2 and 1. Both consisted mainly of random encounters. The players got horribly sick of kobolds really fast, and I fudged a bunch of random encounters with orcs away or the same thing would have happened with them. The traps were useless; the only time a trap came into play was when I got frustrated and had a kobold bull rush the gnome guide into the pit so I could being out the giant centipedes. (Which were pointless, because dwarf.) The rogue auto-spotted every trap every time. As written, the Chapter 1 boss can't be beaten unless the PCs have at-will spells, and is automatically defeated if they do.
- The only fun encounter was the gelatinous cube. And I don't just mean that because it was the only encounter to almost kill a PC (or present a meaningful threat at all), but also because it was the only one where an enemy had an interesting and useful ability. The kobold dragonshields looked promising, but the kobolds were so fragile that their ability didn't matter. The blind ogre failed (couldn't hit, couldn't hide, was easily spotted and outrun). The stirges failed (out of 6, only 3 got to attack before they were killed, one hit, and it was parried--which left us with the ludicrous image of a stirge that stuck its proboscis in someone without having inflicted any damage).
- Self-healing was surprisingly effective, but the party hardly got hurt, again except for the wizard.
tl;dr: Monsters were boring and mainly too easy, wizard and cleric were boring. Both fighters were good. The rogue was just strange. No one brought a sorc or warlock, unfortunately. Hard to evaluate healing other than self-healing (which was good) given how easy the fights were. A better adventure would probably have helped a lot.
"Edison didn't succeed the first time he invented Benjamin Franklin, either." Albert the Alligator, Walt Kelly's Pogo Sunday Book
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