Innovative Vehicle Elecronic Control System (INVECS) is the name given to Mitsubishi's self-learning automatic transmissions.
INVECS II which features on Third Generation models no longer has power and economy modes but instead monitors your driving style, and after a short period sets the up and downchange points to suit. Downchanges usually occur, especially when rolling down a hilly road while breaking and are less likely to change when going up a steep hill while the lever is in D.
Even though INVECS II transmissions can have tiptronic functionality, not all of them do. TE,TF,TH and Early Series TJ models didn't. All Magnas from TJ Executive series 2 (May 2002) and beyond had tiptronic as standard. All Sports and VR-X models had tiptronic as standard.