Three codes were hidden in the WITNESSING THE MIND PALACE post on the Investigate Ingress blog.

[1] 2xjn3easyb2r7r

[2] 9e34scir8hqxhhtm

[3] <!!<%^!!<%%%<%%!<!!<%%!%<%%%^<%%%!^<%%%!!!<%%!!!<%^!!!<%!%<%%<!!!<%%^!!<!!<%%%^!!

Code #1

Observations

Everything is there but why does it return invalid ?

Spoiler

16 characters with the right amount of numbers for a valid passcode

Spoiler

Make a 4×4 grid

Read going down from the upper right 4

4rxm3iqtechh9s8h

Find the split character. Why do you have only 4 distinct characters

Spoiler

The only character that is never repeated is <, let’s use it has a split

<!! <%^!! <%%% <%%! <!! <%%!% <%%%^ <%%%!^ <%%%!!! <%%!!! <%^!!! <%!% <%% <!!! <%%^!! <!! <%%%^!!

Look at the distribution, especially the !, they sometime are in triplets. Looks like roman numbers.

<=L %=X ^=v != 1

52 67 80 71 52 79 85 84 83 73 68 69 70 53 77 52 87

Convert decimal to Ascii

4CPG4OUTSIDEF5M4W