Cubi tentacles morph from their wings, and come in degrees:

Cubi tentacles also substitute improved unarmed attack as a prerequisite for Improved Grapple

Cubi tentacles I:Edit

Your tentacle reach is as if you were one size category above your current one. you can attack for 1d6 damage, or use them for relevant skill checks for a DC +5

Cubi tentacles II:Edit

You can now make two 1d6 damage attacks, and skill checks have DC+2 . You gain +2 to grapple, disarm, and trip checks.

Cubi tentacles III:Edit

You can now make 4 1d6 attacks, and skill checks have DC +0. You gain +5 to grapple disarm and trip checks (replaces previous).

Cubi tentacles Crit 20 x3

Live clan leaderEdit

If your clan leader is alive, your tentacle tips have heads on them

your damage per attack is 1d8, and with your tentacles out, you automatically gain the effects of the Combat Awareness feat

Also your crit threat range expands to 19-20