i have a brief explanation on my previous post https://moot.us/lounges/73/boards/289/posts/2593402/endless-duel-4-who-is-who
also there is a youtube link there on me going through all the tiers
most of the game stuff are server side, pretty sure that isn't technically possible unless it is an offline game, and to answer your question anyway, you can't since it has something to do with security or hacks or whatnot.
Back in the early days of gacha, there were games that allowed this, and if you have the perfect internet and two synced devices, you can end up with two items if you open a single ticket from both devices at the same time.
I used to buy Devil Pass until Season 11, didn't buy anymore after that, I bought it due to the skins that gave extra value for me.
imho, it is still worth but recently they have introduced packs to us that gave so much onyx but area really cheap, I moved my spending to those as I specifically want onyx more, I do friend battles for extra stamina daily and hoard them for hot time or narratives depending on schedule.
Nah man, I just dedicate time to this game.
Anyway, I have singled out a few choices for it as follows:
Tyche, Bremen, Davi, Lisa, Mona, Judas, Tartarus?, Hecate, Tiamat, Alecto?, Pompoms?, Baal?, Apollo?, Eris?, Cu Sith?, Skuld?, Azure Dragon?, Shamash, Demeter, Euros, Hypnos?, Vesta?, Deino, Leuce, Goga, Ptah?, Seshat?, Morgana, Salmacis?, Bazooka?, Mnemosyne, Fighter?, Daron?, Mimic, DJ Hertz, Dark Watcher?, Light Watcher?, Messenger?, Teddy?
I am less certain for those who has question marks and I am more inclined currently to getting more tanks and healers, same strategy as what I wanna pull off to 5* category. At least 5 tanks and 6 healers
No, any more sources based on what you listed are from paid stuff already, you can get stamina from the devil pass free side too.
My suggestion is to keep up with the timeline, plan well your stamina usage so you don't get surprised by a narrative, it happens in this sequence, Narrative, Ragna, World Boss, and repeats
https://www.youtube.com/channel/UCSl5XaH5Gmw8qmfUA_haHcw
you can check Official ESTIMATE too, part of Shift Up
https://www.youtube.com/watch?v=18qqLd20yyA&t=
this guy has uploaded some of the music on youtube
Bathory, Chang'e, Dana, Two-Sided Moa, Neptune
Make Dana and Neptune top attack and Chang'e very close as 3rd, stack HP and DEF as carta for the whole team and if needed, HP ATK carta to play with the ATK stats.
This was my setup when I was using Hades for top 100
Use ATK AGL equips and HP DEF armor for everyone.