New Chess Engines Caissa, Crystal, Patricia, and Viridithas are Now on Chessify

As the leaderboards of top engine championships and computer chess rating lists continually evolve, our vibrant Discord community quickly spots each promising new engine and urges their inclusion on our platform.

This time, we're excited to introduce not one, but four new engines at once: Caissa, Crystal, Patricia, and Viridithas. Now featured on Chessify's Analysis Dashboard, these engines are available to everyone for free, and you can use them at a basic speed of 1000 kN/s without any need for account registration.

In case basic-speed analysis does not meet your chess ambitions, you have the option to supercharge these engines to a blazing fast speed of up to 130,000 kN/s (kilonodes per second) using Chessify coins and subscription plans. This substantial increase allows for deeper and faster chess analysis, meeting the needs of even the most demanding players. You can find more info on speed options below, but first, let's have a brief look at the unique capabilities of each chess engine to help you pick the perfect one for every challenge on the chessboard.

1. Caissa 

- Version used on Chessify: Caissa 1.20.1 (best dev version)

In development since early 2021, Caissa has risen to become a formidable chess engine, now ranked No.7 in the world according to the CCRL rankings as of September 1, 2024.

The Caissa team has developed their own neural network, trained with self-play games using a custom trainer. Originally based on Stockfish's network, Caissa's first version was much weaker due to its smaller dataset—a few million positions. However, starting from version 1.18, Caissa has been using over 12 billion newly generated positions, significantly increasing its strength.

Further technical specifications of Caissa are available on its official GitHub page.

2. Crystal

- Version used on Chessify: Crystal 8

Crystal is a Stockfish-derived UCI chess engine which is known as a certified problem solver. It tackles the significant challenges of aggressive reductions and pruning, which can sometimes lead to positional or tactical oversights. A standout feature of Crystal is its enhanced ability to detect fortresses in chess endgames. Since September 2020, Crystal has also incorporated NNUE evaluation to further boost its effectiveness.

So if you're dealing with tricky endgame positions or needing to double-check missed opportunities by other engines, then Crystal is the way to go.

Examples of Crystal's capabilities include:

• • (Draw) 4K1bn/5p2/5PpB/6P1/3k4/8/8/7q w - -
• • (f6) rk6/pP1p2p1/B7/3K1P2/8/8/7b/8 w - -

Learn more about Crystal's technical details on its GitHub page.

3. Patricia

- Version used on Chessify: Patricia 3.1

Dubbed "the most aggressive chess engine the world has ever seen," Patricia lives up to its reputation with an EAS score of 430,000, a benchmark for measuring the aggressiveness of chess engines. To put it into perspective, the average engine’s EAS score ranges between 50,000 and 100,000, while Stockfish’s score stands at 190,000.

Although its ranking among chess engines isn't very high—No. 147 in the world—Patricia boasts a rating well above 3000, making it a formidable opponent against any human player. So the next time you need to crush your opponent, turn on this "Killer Bunny" to get bold and aggressive move suggestions.

For more technical details on how Patricia earned its reputation as the most aggressive engine, visit its GitHub page.

4. Viridithas

- Version used on Chessify: Viridithas 14.0.1

Viridithas is one of the leading chess engines with its rating exceeding 3900. As of September 2024, it holds the No. 17 spot in the world in classical chess and ranks in the top 10 for Fischer Random Chess.

The Viridithas project distinguishes itself by using original training data for its neural networks. Thanks to its datagen code, Viridithas is able to generate diverse game scenarios without relying on traditional opening books. Such an approach to data generation ensures a variety of gameplay during the engine's training which leads to even greater strength.

Discover more about Viridithas and its features on its official GitHub page.

Did you know? A significant number of Chessify's new features and engines are being offered by our Discord community. Become a member of our Discord server as well to send us your suggestions and get quick help from other Chessify users.

Cloud Server Speed Options for the New Chess Engines

The new Caissa, Crystal, Patricia, and Viridithas chess engines are available for free on Chessify's Analysis Dashboard at a speed of 1000 kN/s (equivalent to 1 MN/s). For those looking to step up their analysis speed and accuracy, Chessify offers powerful cloud servers capable of reaching up to 130 MN/s.

Here's the list of the available server speeds and their corresponding subscription levels or coins rate:

• • 1 MN/s (1000 kN/s) - Free
• • 10 MN/s - Amateur Plan ($7.99/month or $79.99/year)
• • 25-100 MN/s - Master Plan ($34.99/month or $349.99/year) and GM Plan ($1200/year)
• • 130 MN/s - Dedicated server, rentable at 10 coins/minute with Chessify coins. Discounts are available for bulk purchases and combo plans.

You can find our detailed pricing and subscription options on our Pricing Page.

Please note that the numbers are approximated and the engines' performance can vary depending on the position.

How to Analyze with Caissa, Crystal, Patricia, and Viridithas Engines Online

You can start using the new chess engines on Chessify by visiting chessify.me/analysis. No registration is required to access Caissa, Crystal, Patricia, Viridithas, and six other chess engines, all available at a speed of 1 MN/s for free.

For newcomers to Chessify, we have video tutorials that will quickly guide you through the process of starting your analysis with our chess engines online. Watch the video below to start analyzing with Chessify's engines online smoothly and efficiently.