I found the free nanDECK software (and tipped via PayPal) after some searching. I also found this three-part series by Dylan Wolf, who put a lot more time into this than I did. That time investment, plus nanDECK's own fantastic manual, got me up and running very quickly.

I started with a Google Sheet document for some condition cards, found here. Alt-enter and copy-pasting the Unicode bullet character let me do quick and easy multi-line text, although nanDECK does support HTML.

The cards are given in front-back-front-back order, for reasons I'll get to in a moment. In addition to these columns, there's a "custom rules" column I haven't used yet.

Now on to the nanDECK script. I created this in the program itself, although it's just a text file

[all]=1-{(name)}
[standardfont]=Consolas
CARDSIZE=8.89,12.7
PAGE=8.89,12.7,PORTRAIT,HVEO,#FFFFFF,[all]
LINKMULTI = num
LINK = cards.xlsx
FONT = Georgia, 20, U, #000000
TEXT = , [name], 0, 0, 100%, 20%
IMAGE = , [img], 0, 20%, 100%, 40%, 0, P
FONT = [standardfont], 14, , #000000
TEXT = , [desc], 5%, 15%, 90%, 30%, left, wordwrap
FONT = [standardfont], 12, , #000000
TEXT = , [prompts], 5%, 45%, 90%, 38%, left, wordwrap
ICON = , T, plus.svg
ICON = , B, error.svg
ICON = , X, like-1.svg
ICONS = , [icons], 0%, 83%, 40%, 20%, 20%, 10%, 0, PN

The [all] macro, CARDSIZE, and PAGE all came courtesy of Dylan. The rest started from nanDECK's own manual, with some adaptions.

Icons made by Smashicons on flaticon.com, specifically this set. The icons are free to use with attribution.

I used the SVG version of the icons to avoid artifacting on resize. To do this, I also had to install Inkscape, and update the Config section of nanDECK with the path to the Inkscape executable.

The resulting PDF can be found here.

An important goal of this process is to make cards that don't look too good. If that's surprising, it's because I want to encourage people to create cards at their own table, and if they compare their hand-written custom cards to the "official ones", I want them to look pretty similar.

The next goal is to tweak this layout, and write a comprehensive deck of cards. I don't know when I'll be able to playtest this game again, but I feel like my earlier goals for this game are now much easier to meet.