Abilities
All abilities and where to get them
Five skills
Arcane Whip comes from The Fallen and is the first special whip skill. Holy Light comes from The Warrior, passes Chaos Shards, and can deflect shots. Smash comes from The Builder after Talos: jump, then down and jump, to break blocks and some floors. Aerial Rush comes from The Artist after Brauner and is the air dash. Double jump comes from The Shadow after the Choir fight with Death.
Chronomantic Dive is Isaac's spell on The Zealot card. It is not a sixth traversal skill. Searches for air dash mean Aerial Rush. Searches about breaking floors mean Smash, and you need The Builder before they work.
Upgrades that are not skills
A full upgrade list also includes 24 Brave Hearts, 24 Wise Hearts, 14 red attack books, and 14 blue defense books. Those are permanent stats, tracked on the collectible pages. They do not open a new kind of door the way Smash and double jump do.
What I ran into
I kept a scratch table of verb to boss while reading, because the card names and the skill names do not match. The Builder is Smash. The Artist is the dash. The Shadow is the jump. That translation is the page.
Questions
How do I break floors?
Smash, from Talos and The Builder card. In the air, press down and jump.
What is the dive?
Chronomantic Dive, the spell on Isaac's The Zealot card, not a traversal upgrade.