@ENAMOR
Sticking to Standard or Expanded Format legal cards and printed* HP scores:
The
highest printed HP for a Basic Pokémon worth only one Prize is 180, and belongs to the Regigigas of which you speak (SM - Crimson Invasion 84/111). The
second highest printed for a Basic Pokémon worth only one Prize HP is 160, and is shared by four different Pokémon: Darkrai [Prism Star] (SM - Ultra Prism 77/138), Giratina [Prism Star] (SM - Ultra Prism 58/138), [Prism Star] (SM - Ultra Prism 62/138), and Solgaleo [Prism Star] (SM - Ultra Prism 89/138). The
third highest printed for a Basic Pokémon worth only one Prize is 150, belonging to Zygarde (SM - Black Star Promos SM48; SM - Burning Shadows 100/147). All are currently legal for both Expanded and Standard Format use.
The
highest printed HP for a Stage 1 Pokémon worth only one Prize is 200 and shared by two cards: Wailord (BW: Dragons Exalted 26/124) and Wailord (SM - Guardians Rising 30/145). The former is only legal in the Expanded Format. The
second highest printed HP for a Stage 1 Pokémon worth only one Prize is 160 belonging to Blissey (SM - Guardians Rising 102/145) and is both Standard and Expanded legal. The
third highest printed HP score is shared by six cards: Armaldo (XY - Steam Siege 57/114), Bastiodon (XY - Steam Siege 70/114), Gyarados (XY - Burning Shadows 33/147), Kabutops (XY - Fates Collide 39/124), Steelix (BW - Plasma Freeze 79/116), and Tyrantrum (XY - Furious Fists 62/111). Steelix and Tyrantrum are only legal for Expanded Format play, and Steelix is a Team Plasma affiliated Pokémon. This is the last time I'm listing six or more cards when they qualify. XP
The
highest printed HP for a Stage 2 Pokémon worth only one Prize is 180 and shared by two cards: Mamoswine (SM - Crimson Invasion 21/111) and Torterra (SM - Ultra Prism 9/138), each of which is legal for both Expanded and Standard play. The
second highest printed HP for a Stage 2 Pokémon worth only one Prize is 170 and is shared by two cards: Aggron (SM - Crimson Invasion 67/111) and Incineroar (Shining Legends 72/83), both of which are legal for Expanded and Standard Format play. The
third highest printed HP score is 160 and shared by almost three dozen cards... I'm not going list them out. XD
The
highest printed HP score for a Restored Pokémon (none of which are worth more than one Prize) is 120 belonging to Aerodactyl (XY - Fates Collide 76/124). It is still Standard Format legal. The rest have 90 HP or less, with some being Expanded only.
No BREAK Evolution is worth two Prizes and all are still Standard legal; while they all count as the same Stage, they can play rather differently based on the Stage from which they Evolve, so I'm dividing them accordingly, but just covering the highest score for each. The
highest printed HP score for a BREAK Evolution that Evolves from a Basic Pokémon is 150 HP, shared by four Pokémon: Ho-Oh BREAK (XY - Black Star Promos XY154), Lugia BREAK (XY - Fates Collide 79/124), Xerneas BREAK (XY - Steam Siege 82/114), and Yveltal BREAK (XY - Steam Siege 66/114). The
highest printed HP scores for a BREAK Evolution that Evolves from a Stage 1 is 160, and is shared by three cards: Acranine BREAK (XY - Black Star Promos XY180), Pyroar BREAK (XY - Steam Siege 24/114) and Trevenant BREAK (XY - BREAKpoint 66/122). The
highest printed HP score for the BREAK Evolution that Evolves from a Stage 2 is shared by three cards: Chesnaught BREAK (XY - BREAKthrough 12/162), Hydreigon BREAK (XY - Steam Siege 84/114), and Machamp BREAK (XY - Evolutions 108/114).
I used the official
Pokémon TCG Database to look all of these up
except Arcanine BREAK; thankfully, I just remembered it existed and that it was pretty beefy.
*Combos can always increase HP scores.