From the back cover of the PDF:
A mythic artifact known as the Crystal Consciousness cycles toward awareness . . . and with its waking, the entire psionic paradigm hangs in the balance. Many seek to control the Crystal: a psionic lich, a band of fanatic arcanists, and a guild powerful in the arts of the mind. Some would use the Crystal to dictate the future of psionics while others would use it to crush the mental arts forever!
In addition to this world-shaking adventure for 10th-level characters, If Thoughts Could Kill details all-new rules from Bruce Cordell, designer of the Psionics Handbook. Inside this award-winning book you’ll find:
New psionic monsters including the psionic lich and a new PC race.
Lots of new items,powers, and even an all-new psionic prestige class.
The new discipline of Psychonecromancy and other variant rules.
More than 300 new powers converted from spells in the Player’s Handbook and The Book of Eldritch Might.
From the introduction:
In this reprinting of the original electronic edition of If Thoughts Could Kill, we have updated the page design to match the look of our current product line, facilitate quick printing, and conserve ink.We’ve also made a few changes to bring the book in line with the newest version of the d20 System Reference Document and included some material from Monte Cook’s website that was featured in the print edition (see appendix).
User summary: This version was offered as a free upgrade to purchasers of prior editions.