Update 10/11/12 6:00 p.m. PDT: PTR status is online.
Patch 1.0.5 is currently in development and now available for testing on the PTR. This patch introduces Monster Power, a new system which will allow you to adjust how challenging monsters are across each difficulty, and the Infernal Machine, an event that will pit players in Inferno against "uber" versions of some of Sanctuary's most nefarious bosses. Patch 1.0.5 also includes several bug fixes, UI improvements, and additional class and item balancing.
PTRs are a very valuable tool for our development teams -- when you participate, share your feedback, and submit reports, we can squash more bugs and ensure that the patch we release is of the highest quality possible. Patch 1.0.5 will mark the first time we've performed a public test for Diablo III, but we’re planning to conduct public tests for most (if not all) future patches.

To participate in the public test, you must have a Diablo III game license attached your Battle.net account that’s in good standing (i.e. it hasn’t been suspended or banned). While the 1.0.5 PTR is only available in English, French, German, and Korean languages, accounts from all regions are eligible to participate.
Step 1: Create a PTR account by logging in to your Battle.net Account Management page. Select your Diablo III game license, and then click "Create a PTR account."
Step 2: Download the client from the Diablo III landing page, or from your Games Download page in Account Management.
Step 3: To play on the PTR, simply launch the PTR client and log in normally. You will be connected to the PTR server automatically.
The option to copy your existing Diablo III characters from your live account to the PTR will be available and can be done directly through the PTR client. However, only one region per account can be copied at a time. So, if you choose to copy characters from your account in a different region, any previously copied PTR characters will be lost.
Step 1: Log into PTR client and create a level 1 character. After you're done, return to the main character screen.
Step 2: Click on the "PTR Copy" button located in the upper right-hand corner. (The PTR Copy button will not appear in-game until you have created a new level 1 character.)
Step 3: Select your region.
Step 4: Click "Copy." This will copy all characters on your account from the selected region.
Step 5: You will be disconnected from the PTR client.
Step 6: Log back in. Your copied characters will be available for play.
Please note that you can only copy characters over to your PTR account once every 72 hours. Attempting to copy characters more than once per week will result in Error 395000.

Further details on how to access the PTR and use the Character Copy system can be found in the FAQ. Once you've had the chance to try things out, be sure to visit the Public Test forums to discuss the patch.
As this is a test server, please anticipate uneven game performance, and note that restarts and downtime may occur without warning. We'll provide information regarding extended downtimes, should they occur, in the PTR Feedback forum.
Note: Even though patch 1.0.5 is not the PvP patch, it does contain files that hint towards what PvP will be like.
PvP MapsNote: The PTR is now available for download
Patch 1.0.5 will soon be available for testing on the PTR. Once the PTR is up and ready, we'll enable posting in this forum and the PTR Bug Report forum so you can share your feedback and report any issues you may experience while playing.
In the meantime, be sure to check out the patch 1.0.5 PTR patch notes and the information below to find out how to set up your PTR account.
How to Participate:
To participate in the public test, you must have a Diablo III game license attached your Battle.net account that's in good standing (i.e. it hasn't been suspended or banned). While the 1.0.5 PTR will only be in available in English, French, German, and Korean languages, accounts from all regions are eligible to participate.
You will also need to create a PTR account by logging in to your Battle.net Account Management page. We will be enabling PTR account creation soon (we'll provide an update once it's available), and once it's up you'll simply need to select your Diablo III game license and then click "Create a PTR account." After you've created your account, you'll be able to download the client from the Diablo III landing page, or from your Games Download page in Account Management.
Please note that will not be able to log in to the PTR client until it's live.
Character Copy:
The option to copy your existing Diablo III characters from your live account to the PTR will become available once the PTR is live. Only one region per account can be copied at a time, however, so if you choose to copy characters from your account in a different region please note that any previously copied PTR characters will be lost.
We'll be providing more details, including an FAQ, once the 1.0.5 PTR is available, so stay tuned!
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