I edited this message because it was too long and not properly focused on the main question that is WHAT'S THE STRONGEST BUILD FOR A SUPPORT IN 5E?
Lore bard or Druid (shepherd/moon)? As buffer/debuffer/god
Divine Soul Sorlock or Tempest Cleric? As healer+dps
Are there some other builds i don't know about?
I'm starting a level 13 shared multi-table campaign, 16 players divided in 4 tables and party composition randomized each week but always 2 melee and 2 ranged. The campaign is gonna be divided in a series of one shot quests, one each week till we reach level 20, so i won't know what players and characters i will play with each time i participate. I think the best way to be useful in a party of strangers is to be a field controller but i need help to find the most performing build, i'm a long time 3.5 player but still new to 5e and never played over level 6, i've read some guides but i'm still not competent and experienced enough in the 5e to come up on my own with a proper build.
I know all the above builds are good viable builds but i don't want a viable build i want one that transform a possibly tpk in a walk in the park when i click the panic button, because a rule of the campaign is if a tpk happens you are forced to leave the campaign and i fucking want to reach level 20.
I'm competitive af and i don't want to leave because of someone else poor judgment of a situation.
I want something broken like a 3.5 planar shepherd, cheater of mystra, incantatrix+arcane spellsurge+malconvoker, bard+dragonfire inspiration+word of creation+sublime chord.
I don't know whom i'm gonna play with and i don't trust the average player, i don't want to always break the game or solve a fight but i want a build that allows me to do it when is needed to prevent a total party kill.