I’m travelling, so this might not be the most thorough or polished review Codex deserves. Don’t take this as a reflection on the game.
The game can be learned in one or two playthroughs, but it will probably sound way more complicated when describing it in words. I’ll refer to Magic: The Gathering (MtG), Hearthstone, and Dominion. If you have absolutely no familiarity with any of these games, you may want to skip the post. But, you don’t have to have played any of them. If you’ve heard of MtG and vaguely know what a deckbuilding game is (Dominion), you’ll probably be fine.
Codex takes the core of MtG as it’s starting point. Each player has their own deck built from various colors. The colors tend to have themes that loosely follow MtG. Red focuses on haste and burn spells. Green is creature and growth spell based. Black uses skeletons and killing off creatures to get effects. And so on.
But that’s about where the comparisons stop. One of the most annoying aspects of MtG for me is that you can only attack the other player with your creatures. The opposing player has all these creatures on the battlefield and can even block with them, but the attacker can’t have their creatures attack them. It makes no sense, and forces really weird play to avoid bad trades. Also, after being damaged, creatures heal for the next turn. This makes healing a totally nonviable type of spell to design around.
Hearthstone basically fixes these two oddities by allowing creatures to attack each other, and damage persists across turns. This is also how Codex works. It opens up so many interesting decisions. Do I heal myself or do I heal my creatures? (It’s actually not that interesting. Answer: Always heal the creatures because your health isn’t as important as board presence).
In all these games, one must pay a cost to cast a spell or summon a creature. MtG builds these costs into the deck by forcing you to have “dead” cards (land). This means you can randomly get flooded by too much or screwed by too little. The ideal would be to play a land every turn to keep ramping up to better creatures until you hit an ideal amount, and then you never want to draw land again.
Since this is the ideal, Hearthstone just forces this to happen by giving you one extra mana per turn. It fixes these two MtG issues in one swoop. You never draw dead cards, and you can focus on strategically playing on curve without being at the mercy of random draw.
In a sense, this goes too far, because it eliminates some of the decision space. Codex draws on RTS games and hits a very interesting middle ground. You pay for cards with gold, and you always have the choice to increase the amount of gold each turn to play on curve. But unlike Hearthstone, there’s a cost to do it. You must convert a card in hand to a “worker.” This removes the card from the game and costs 1 gold, a startlingly high cost that after a few games becomes clear to always be worth it.
The more decisions that have to be made, the higher the skill cap. This one choice each turn is very interesting. Do you forego making a worker to have better card advantage, and 1 extra gold this turn; or is this too risky because the next turn your opponent will have more gold if they make a worker?
Another RTS innovation that increases the decision space is building tech buildings. Each turn you get to add two cards to your deck from a pool determined by your starting factions. This is the Dominion deck building idea. The point of this is that you can try to predict your opponents strategy and then add in cards to your deck to counter them. But maybe they were only feigning a strategy and you teched in a counter which they already countered. The mind games are real.
If you haven’t built any buildings, you can only use cards coming from Tech 0. If you spend money to build a building, you get to use Tech 1 cards and so on. This is often the hardest decision in the game for me. Tech 2 cards are really, really powerful. If one player starts playing them significantly earlier than another, they will probably spiral out of control to victory.
But building the structure to play these powerful cards pretty much wrecks a whole turn. In other words, if you build these too early, you might incur a cost so severe you fall behind and can’t catch up, even with the powerful new cards. If you build it too late, your opponent might just win with their powerful cards. It’s a super interesting and critical decision that has to be made by comparing economies, board state, card advantage, your current strategy, your opponent’s strategy and so on.
The last interesting innovation I’ll talk about is the fact that you have to have a “hero” in play to cast spells. This opens up a huge range of possible targets for attack. Do you kill the hero and cripple their ability play spells? Do you attack creatures for board advantage? Do you attack tech buildings so they can’t play their more powerful cards? Do you all-in and only attack the base in hopes of rushing a victory?
And this is only the half of it. There’s a board, so creatures can take up strategic positions. Heroes have abilities they get from levelling up. Some of the innovative card keywords are really clever, like Purple being about time manipulation. And I’m sure I’m missing dozens of cool ideas they’ve packed into this.
I’ll admit it is quite expensive to get the full thing, but it’s not a collectible or trading card game. The set is complete as is (and considering it’s priced at about 2 booster boxes of MtG cards, i.e. 1/(10,000+) of the cards in MtG, it’s hard to complain). Once you have all the cards (which come in the Deluxe version), you’re done buying cards for the game forever. The Core Set is priced at a standard board game price and gets you the complete Green and Red sets, and if this is interesting to you, you’ll get more than enough hours of play to make it worth it.
Overall, I couldn’t be happier. It’s like this game was designed specifically with me in mind. The game is really fun at a casual level, but really deep. I could see the game becoming quite competitive with how high the skill ceiling seems to be.