Persona 4 Golden executes the "Myriad Truths" bit at the end of the True Ending in a rather unusual way.
It first removes all of the player's Personas, and gives them a special Persona named "Okami" in the code (i.e. not the NG+ exclusive Izanagi-no-Okami), which has 16 in all five stats and only two skills - "Infinite Endure" (which is how the player character survives the final boss's scripted attacks), and Myriad Truths.
I'd imagine the same sort of thing is utilised for P3/FES's final attack, and for P5/R's Sinful Shell, but...neither has been officially ported to the PC, so I can't exactly use Cheat Engine and a ready-made template thingy for them...
(A few more Persona oddities is that while Shiva exists in both Persona 2s, P3, P4, P5, and both PQs, his unique skill "Pralaya" doesn't exist in P5 or P5R for some reason despite being in all those other games; P5 and P5R also have numerous 'beta' skills named "Megidolaon", with the base game having four, and Royal adding a fifth, for whatever godforsaken reason. One of those is used for the Attendant's 9999-damage fight-ender, but why do the others exist?)
It first removes all of the player's Personas, and gives them a special Persona named "Okami" in the code (i.e. not the NG+ exclusive Izanagi-no-Okami), which has 16 in all five stats and only two skills - "Infinite Endure" (which is how the player character survives the final boss's scripted attacks), and Myriad Truths.
I'd imagine the same sort of thing is utilised for P3/FES's final attack, and for P5/R's Sinful Shell, but...neither has been officially ported to the PC, so I can't exactly use Cheat Engine and a ready-made template thingy for them...
(A few more Persona oddities is that while Shiva exists in both Persona 2s, P3, P4, P5, and both PQs, his unique skill "Pralaya" doesn't exist in P5 or P5R for some reason despite being in all those other games; P5 and P5R also have numerous 'beta' skills named "Megidolaon", with the base game having four, and Royal adding a fifth, for whatever godforsaken reason. One of those is used for the Attendant's 9999-damage fight-ender, but why do the others exist?)