SolForge is a digital trading card game that I like to play. In it, players build 30 card decks, draw 5 new cards each turn and typically may only play 2 of those 5 cards per turn. The core mechanic of the game is that cards that are played are “leveled up” - in other words, a typically more powerful version of the card appears the next time your cards are all shuffled together. In this way, cards get more and more powerful over time, while some cards stay at the same level if you don’t really play them. Currently, all cards have three levels they can reach.

Obviously, one of the big strategic elements of the game is choosing what cards to play each turn. Making the right choices have a real impact on the game. Level up the same cards and you’ll end up with a few powerful cards early on, but you’ll have a greater chance of drawing your lower level cards. Level up a variety of cards to level 2 and you might not have an answer to something your opponent plays in level 3.

I’ve been thinking a lot lately about how each time you play out your turn, there’s an opportunity cost associated with the cards you didn’t play. Some cards get significantly more powerful as they get to a higher level. Some cards don’t change all that much level to level. And some cards lose a sizeable amount of utility if they aren’t leveled up right away.

A powerful removal spell in SolForge is a card called Dreadbolt. At level 1, the card targets any level 1 creature and deals damage to it equal to that creature’s attack. Many of the biggest threats have a high attack, so it’s a pretty good removal spell. At each level, the card gains the ability to target that level’s creatures. A level 1 Dreadbolt can target only level 1 creatures, level 2 Dreadbolt can target level 2 or level 1 creatures, and, at level 3, it can target any creature, one of the few somewhat reliable ways of answering many powerful level 3 cards.

There’s another factor to consider: you can’t actually play and level up Dreadbolt unless there’s a legal target. When all creatures are at level 1, you know Dreadbolt is going to hit something. When cards start reaching level 2, there’s less of a chance a level 1 Dreadbolt can hit something, which makes it harder to level up, which makes it less likely its a useful card each time you draw it. Eventually you may get to the situation in which Dreadbolt may never have another target to play and has to sit in your hand each time you draw it.

(Edit: I’m a little embarrassed to say that I didn’t know you could level up a card by discarding it as one of your actions. That certainly helps situations where you don’t have legal targets! I wish I knew about that sooner. Thanks to reddit user McAzazel for the tip.)

In my mind, the opportunity cost of not playing Dreadbolt is fairly high at level 1 and gets higher as the game goes on. As powerful a card it is, there’s a real draw back to not getting in your Dreadbolts when you can. The variance of the card is part of the reason they can make the card as-is.

Take another spell - Lightning Spark. Lightning Spark is a spell that is always “live” because it can target both creatures and players and deal damage (5 damage at level 1, 8 at level 2 and 12 at level 3). Even if there are no creatures in play, you can always toss Lightning Spark at your opponent’s face. Unsurprisingly, however, the power differences between level 1 and level 3 is not as large as it is for Dreadbolt. That means that not playing Lightning Spark is less of a risk, all else being equal. If I draw a hand that includes a Dreadbolt and Lightning Spark and either one will get the job done, I’m more likely to play out the Dreadbolt for this reason.

Of course, sometimes having a level 2 Lightning Spark is better than having a level 2 Dreadbolt. Sometimes getting creatures on the board is better than playing a removal spell. Knowing when to use certain cards and at what time is part of the skill in SolForge. But when evaluating what play you are going to make that turn, consider the costs involved when you don’t play a card and use it to help make your decision. I like to ask myself, “Will this card still be relevant later in the game if I don’t play it now?”