The player options here are hilarious, and most definitely not suitable for play at more serious tables. In addition to player options that are simply goofy (like a Druid whose Wildshape form will always appear to be a raccoon, regardless of its actual stats) there are player options which enable and encourage disruptive behavior (such as a Rogue "Meta-Thief", who gets to keep all magic items found by the party unless another player challenges them to a game of Dungeon Mayhem .) As a player, you're more likely to draw enjoyment from this guide by reading it and laughing at it than you are to actually use any of its subclasses in play.

First off, I love the concept of this class. It's always great to have Warlock patrons that embody principles besides evil and chaos, and Mechanus is a fun and under-used bit of D&D lore.

As for the abilities you get, they're not the flashiest nor the most powerful Warlock patron abilities out there, but they are definitely on theme, and they're useful for Warlocks of any Pact.

Some things I might have liked to see: a few Eldritch Invocation options, a distinct familiar for pact of the chain (a tiny modron-like construct?) It's always nice when a subclass option includes some extra bits.

Eberron is an alternate Dungeons and Dragons setting, introduced in 3e and also officially supported in 4e, which is distinguished by the ubiquity of low-level magic, and its integration into everyday life, mainly via tangible objects: trains powered by magical electricity, lanterns powered by magical fire, etc. There's more to it than that, but I'm not going to describe the setting in exhaustive detail in this review.

This document is intended to give players and DMs what they need to start running campaigns and adventures set in the Eberron world. It's a good first step, but it's by no means complete yet. I acknowledge that this is a living document, wich will be getting free updates, but this review looks at what you get on day one.

There's a brief overview of Eberron's history, geography, and culture for the benefit of people who are new to Eberron. There's just enough background to give players some context as to how they might want to create and play their character. The document goes into a bit more detail on the city of Sharn, and has numerous random tables for suggested plot hooks. The document emphasizes that Eberron's setting is meant to support the kinds of stories that dominated the pulp magazines in the 1920s and 1930s: swashbuckling high adventure, and hard-boiled noir.

In addition to background material, the book contains hard rules for Eberron's four distinctive races (Warforged, Shifter, Kalashtar, and Changeling) as well as rules for Dragonmarks and some additional magic items. This material all seems pretty good; the four races all have distinctive abilities and stories. Some of the racial abilities (especially the Warforged's integrated armor) seem a little overpowered right now, so I expect that community feedback will sand those down a bit.

It's notable that there are no new classes or class options in this document. The Artificer is the most obvious omission, considering its import to the setting as a whole. I believe it will be added in the coming weeks or months, but it's not here yet.

In summary, you're getting a LOT of Eberron right now in this book, but you're not getting absolutely everything. But, on the balance, I think it is definitely worth it to pick it up now.