Patches for Sale.

Ah sorry. On mobile so when I see a short link, I just assume the worst.

OT: Not sure how I feel about this dlc since I am not proficient enough in chess to make a judgement call. Looks like this should have been a patch but I can't say much.

It's not a matter of difficulty settings. Taking what they say on the store page at face value, this is a revamped version of the engine. Playing at the highest difficulty settings on a single core is still going to be easier than doing the same on a multi-core. More speed, more calculations mean, as Movac already explained to you, a smarter opponent.

Chrome user here :<
The only thing that I'm using is lightshot :|

Sure, I'm not against that. if you buy the whole program, you'll get everything that was mentioned right out of the box. THIS however is a DLC aka a purchasable patch, that updates the game to a new 64-bit engine.

But is the game just the same with this DLC? As far as I know, yes. It's the same, but with a better, more optimized 64-bit engine.

Is it a problem? Of course it is. Why do you want to pay twice just to get better fps from that game? It's not a rerelease.

Here's the thing about rereleases, definitive editions and HD releases. Take Deus Ex HR for example. It had DLCs in the past, sure, but in the Director's Cut edition, not only did they added all DLCs for free, but also updated the game significantly with major bug fixes, level redesigns, smarter AI and extras.

Now, the engine updates.

Shadow Warrior (2013). While the game's new version 1.5.0 is pretty much the same, it has an engine update: 64-bit mode and 32-bit mode.
32-bit mode had some optimization techniques, but it reached the limit where they can't optimize the game further, but it's still available for those who still own a 32-bit machine. 64-bit version however comes with better performance for 64-bit OSs thanks to more optimization techniques, which is why it runs at 60fps max on my mid-end rig.

This game however doesn't have that option, they released the 64-bit version behind a paywall. So if you want better fps, pay another 20$.