The Puzzle Post no. 1 · week of 12 October 2026 · this week

1. Word ladder

Change one letter at a time to turn COLD into WARM. Every step must be a real word. It takes 3 steps in between.

COLD → ____ → ____ → ____ → WARM

2. Number pyramid

Each block is the sum of the two blocks underneath it. Fill in the blanks.

3. Who has which pet?

Ana, Ben, Chi each have one pet: a cat, a dog, a fish.

• Ana does not have the dog.
• The person with the fish is not Ben.
• Chi has the cat.

4. What comes next?

2, 6, 12, 20, 30, ____

5. Riddle

I have keys but open no locks. I have space but no room. You can enter, but not come in. What am I?