Back from the dead.
It's been over 2 years since the last update. Most folk would probably think this project abandoned, which is entirely fair. However, it was more like... put on administrative hold, though I never truly stopped working on it.
In any case, what matters is Deck Fury is still alive, and this update brings massive overhauls, new content, new everything really, turning it from the somewhat half-baked tech-demo from 2 years ago to something far more complete in experience, though there is still much to go.
Let's get started.
Deck System Overhaul
In the previous iteration, the deck system was essentially incomplete - you could slot in any card you wanted into the magazine and there was minimal 'strategy' aside from card order to play around with. Cards were drawn randomly and discarded every single turn so there was no real way plan your plays ahead of time. All this has been changed with a number of new mechanics.
Capacity
All cards now have a capacity cost associated with them, and you begin with a maximum of 5 capacity at the beginning of the game, though this can be increased or decreased by items or other effects.
Your magazine still has a maximum of 5 slots, however depending on the capacity cost of your cards, you may only be able to load 3 or 4 cards.
Capacity is now the primary constraint, preventing you from loading 5 powerful cards into your magazine without drawback.

Overhauled Draw/Discard System
Previously, you would draw an entirely new hand every time you opened the card selection. This is no longer the case. Now, Once you've drawn a hand, those cards remain persistent in your card select until you decide to load or dump them (more on dumping later). The next time you enter the card select, cards are only drawn to fill in empty slots left by your previous turn or until there are no more cards in the draw pile.

Dumping
There is now a 'Dump' button in the magazine UI, which when pressed, discards all cards currently inside the magazine and forces a new draw immediately. This mechanic was implemented as a way to fix the lack of card cycling in this game, as there aren't any cards that actively draws or discards cards, which kind of wouldn't work with the way the game is designed currently anyway.
The dump button is your solution for when you have a weak draw, or want to fish for a specific combo in order to finish off a difficult enemy quickly. It however has limited uses, though you can increase the number of dump charges you have access to through items or events.

Card Attributes
Exhaust - once loaded into the magazine and confirmed, is sent to the exhaust pile and cannot be redrawn through normal means until the end of combat. Anyone who's played Slay the Spire should be pretty familiar with this one.
Fleeting - this one essentially inverts the draw/discard system. Cards that are fleeting will be immediately discarded on turn start if it is not loaded into the magazine.
Modifier - this is a completely new type of card implemented into the game. Unlike regular cards, Mod cards cannot be used in combat and instead apply modifiers to other cards in the magazine. These cards require correct ordering in the magazine in order to take effect, though the UI will tell you when a Mod card is inactive and also show you which cards it is currently affecting.

Using the White Capsule (If you know, you know) mod card to give Rain of Bullets the ability to stun.
Shields
Previously, shields were essentially a very simplistic second health bar that blocked damage from getting to HP, though could be pierced with Pure damage. Now, shields play a much bigger part in combat and need to be paid attention to if you want to kill shielded enemies quickly.
- - Shields now regenerate 10% of their maximum value every second until cracked (reduced to 0). This regeneration is constant, so you need burst damage to get through high amounts of shields quickly, or use cards with the breaking element.
- - Cracked shields take 10 seconds to regenerate, at which point it will instantly regenerate to full.
- - Shields can be instantly cracked by cards with the breaking element. Previously cards with the breaking element only did 2x damage to shields. This makes breaking cards crucial when dealing with heavily shielded enemies.

Overhauled Map Generation
The zone generation system has been rebuilt from the ground up - zones are now far more visually interesting alongside being more interesting to traverse.

Meta Progression
Deck Fury now has meta progression! Unlock new cards and items to find in future runs by gaining (the very creatively named) unlock points, which you gain by simply playing through runs, win or lose. The amount of unlock points you gain is directly tied to your Total Score, thus if you want the most unlock points per run, you'll want to make sure you try to get those special point bonuses any time you're playing through combat stages.

Upgrade Tokens
Upgrades are naturally an important part of the player's power scaling throughout the game, but it's particularly important in Deck Fury due to many cards having multiple upgrade paths, some upgrades potentially drastically changing the functionality of the card and what it can do, allowing you to further specialize your deck or patch up a weakness.
You can now purchase upgrade tokens from the shop and occasionally find them through events, which grant you an additional upgrade point when at an anvil.

Event Stages
Mystery nodes are now worth going to! previously, mystery nodes simply selected randomly between a combat, rest or shop stage. However, now going to a mystery node is only way to enter Event Stages which are either mini-game stages or classic 'choose-1-of-3' events where you can get extra items, stats or money. Currently there's only 3 unique event stages, though there will of course be more on the way.


New Cards, New Items, New Enemies, New Visuals, New Everything
This post is already getting too long, but suffice it to say, there's a lot of new things since the last update. pretty much everything's been overhauled from the ground up to be bigger and better. There's simply too much to go through, but the most important changes have been shown, the rest is up to you to discover.