Use the rules for psionics as described in the Complete Psionics Handbook and The Will and the Way, with the following modifications.

Contact

Contact is no longer a telepathic power; it is a general nonweapon proficiency. Contact covers the rudiments of training in telepathic links and defenses against such.
Psionicists gain Contact as a proficiency automatically; it’s part of their class training.

Wild talents may choose Contact as a nonweapon proficiency (1 slot). Choosing Contact gives you one defense mode of your choice. You gain an additional defense mode at level 3, and another at level 5. Non-psionicists without Contact have naturally closed minds but have no defense modes with which to ward off psionic attacks. Such characters must use the Psychic Defense nonweapon proficiency to have any defense.

Typically, you do not make proficiency checks with Contact; use an attack mode to force contact on a closed mind. You can use Contact to establish contact with an open or undefended mind without making a telepathic attack, though.

Powers that have an initial cost of Contact require you to establish contact before you can use them. You must do so either by paying the Contact PSP cost against a defenseless mind (see the Contact PSP Cost table), or by using a telepathic attack mode to force contact.

If you roll a wild talent and you gain a power that requires Contact as a prerequisite, you gain the Contact nonweapon proficiency for free. This does mean that you gain defense
modes of your choice automatically as well. Remember that using defense modes costs
PSPs. See the relevant descriptions of the powers in The Complete Psionics Handbook.

Contact can be taught by a psion of 5th level to another unopened mind or wild talent for free. See the general rules as per a fighter training weapon proficiencies to non warriors.

Attack Modes

The telepathic attack modes (psionic blast, mind thrust, ego whip, id insinuation, and psychic crush) are general nonweapon proficiencies and are learned automatically by psionicists as they gain levels. A psionicist gains an attack mode of your choice at each level where a new defense mode is learned. Other characters who have the Contact proficiency may learn attack modes as general nonweapon proficiencies. Non-psionicists may learn up to three attack modes in this fashion. Remember that using attack modes costs PSPs. See the relevant descriptions of the powers in The Complete Psionics Handbook.

Power Score Bonus

Psionicists gain a bonus equal to ½ their psionicist level (rounded down) to all power scores, including attacks and defenses. This reflects their training and refinement of their abilities. You may still use your power choices or meditative study (see The Will and the Way pp. 58-59) to improve your power scores further.

General Nonweapon Proficiencies (Psionic Attack Modes)
Nonweapon
Proficiency
Slots Relevant
Ability
Check Modifier PSP Cost
Contact 1 Wis 0 See Contact
PSP Cost
table
Mind Thrust 1 Wis -2 2
Ego Whip 1 Wis -3 4
Id Insinuation 1 Wis -4 5
Psychic Crush 1 Wis -4 7
Psionic Blast 1 Wis -5 10

Psionic Defense Modes
Defense Mode Relevant Ability Check Modifier PSP Cost
Mind Blank Wis -7 0
Thought Shield Wis -3 1
Mental Barrier Wis -2 3
Intellect Fortress Wis -3 4
Tower of Iron Will Wis -2 6

Contact PSP Costs Against Undefended Minds
Level or Hit Dice of Target PSP Cost
1-5 3
6-10 8
11-15 13
16-20 18

Psionic Power Score Bonus: ½ psionicist level (rounded down)

Telepathic Combat and Mental Armor

Telepathic combat uses the rules presented in The Complete Psionics Handbook p. 25.

The Mental Armor nonweapon proficiency from the revised Dark Sun rule book is not
used. If you have a character who has the Mental Armor nonweapon proficiency, you
may exchange this for a different nonweapon proficiency.

Important Reminders

Some rules that are very important to
remember:
● To make telepathic contact and use
most telepathic powers on a
defended target, you must establish
three tangents. You gain a tangent
each time you successfully use a
telepathic attack power against a
closed mind.
● You can only maintain tangents
against one target at a time, and
maintaining tangents costs 1 PSP.
● When you activate an attack mode,
you make two attacks with it. It’s
possible to gain two tangents in one
round. See “The One-Two Punch”
on p. 25 of The Complete Psionics
Handbook.
● When you activate a defense mode,
you gain the benefits of that defense
mode for the entire round. Each time
you defend against a telepathic
attack in the round you may make a
new power check against the attack,
but at any time you may decide to
“stand” on a roll and use that as your
check for the rest of the round. See
p. 26 of The Complete Psionics
Handbook.
● When you activate a defense mode,
you can still activate one other
psionic power in the same round.
● In a psychic contest, victory goes to
whoever rolls higher without going
over their power score. For instance,
if Shanav has a power score of 13
for her ego whip power, she must
roll a 13 or less to activate the
power, but she must roll more than
the enemy’s defense roll for the
power to strike. If she rolls above a
13, she fails to activate the attack. If
she rolls below the opponent’s
successful roll, her attack bounces
harmlessly off the enemy’s defense.
● You only pay the Contact cost if
you’re contacting an undefended
mind. Against a defended mind, you
must make contact by using
telepathic attacks to gain tangents
until you reach three tangents and
force full contact.

Player Tips

● Of the defense modes, mind blank is
the only one that can be used when
you are out of power points; mental
barrier and tower of iron will have
the easiest power scores; and only
intellect fortress and tower of iron
will protect an area and thus defend
your allies.
● Of the attack modes, mind thrust is
the cheapest and easiest to use
(lowest check modifier penalty), and
psionic blast is the only one that
affects an area and thus can hit
multiple targets.
● Since all non-psionicist PCs in
DARK SUN are wild talents, taking
the Contact nonweapon proficiency
is a simple way to acquire some
defense modes, in case you’re
telepathically attacked.