Meta concept by Charles Steinhardt, with crossword grid construction and advertisement design by Eli Bogart, invisible ink development and printing by Ben Buchwald, and interaction script by Miriam Gershenson. Ad space courtesy of Eric Mannes and mitBEEF.
Your Agent 99 meta answers are AD IN TECH, FOLD-IN, and ACETIC ACID. When you take the paper with the supermeta, circle the words that appear in the Tech, fold it to align two columns of the crossword grid, and apply vinegar to it, the circled, indicated letters spell INVESTMENTS IN KAOS.
Credits: The mid-round character interaction which eventually yields the grid was written by Miriam Gershenson, organized by Halimeda Glickman-Hoch, and performed by Miriam Gershenson, Karen Rustad, David Reiley, Sean Lip, Tom Lawler, Yuri Lin, Josh Alman, Alex Dehnert, Stephen Face and others.