Tamagotchi Power (たまごっちパワー), abbreviated as TMP, is a function used exclusively on the Tamagotchi Osutchi and Mesutchi.
The TMP Icon is the located at the middle of the bottom row. TMP is represented by a row of crowns, and is representative of the "tier" of the Tamagotchi raised. The first screen of the menu shows that TMP tier the current Tamagotchi is in, and the second screen shows the current Generation.
There are four tiers of TMP, and each time two adults of the same TMP marry, the resulting babies will always be babies of the next tier up. However, if one adult is of a lower tier, the babies will have a 50/50 chance of being born into either TMP lineage. For example, marrying Kabutchi (TMP3) to ChoHimetchi (TMP4) will result in either PuchiChocotchi (TMP3) or PuchiTeletchi (TMP4).
Marrying ChoMametchi (TMP4) and ChoHimetchi (TMP4) will always produce PuchiTeletchi (TMP4). If a teen evolves into Sutebotchi or Tsuketchi, they will maintain their current TMP tier, but can't marry.
Marrying TMP1 and TMP2 adults works slightly differently. In addition to the TMP level, it also checks between two different groups of adults:
If the adults married are of two separate groups and separate TMP levels, they have a 50% chance of producing Teletchi, and a 50% chance of producing Kuritchi. Marrying Marumimitchi/Mimikotchi to a TMP1 adult has a 50% chance of producing Tsubutchi (Group A) or Kakutchi (Group B), and a 50% chance for Kuritchi.
If a child or teen character from TMP2 or higher receives sufficient neglect, they may regress and evolve into a teen or adult character of the previous TMP tier. Adults that evolve from TMP regression wake at 11 AM and sleep at 11 PM.