[RPG] Does Indomitable let you reroll Saving Throws with Advantage

The easiest way to gain advantage on a death saving throw is to use inspiration.

If you have inspiration, you can expend it when you make an attack roll, saving throw, or ability check. Spending your inspiration gives you advantage on that roll.

Alternatively, you could be a Wild Magic Sorcerer, and use Tides of Chaos. Well, probably.

Starting at 1st level, you can manipulate the forces of chance and chaos to gain advantage on one attack roll, ability check, or saving throw.

The 3rd- level spell Beacon of Hope explicitly grants advantage on death saving throws for its duration.

Fighters can use Indomitable to reroll a failed saving throw - not precisely the same as advantage, but pretty close.

Beginning at 9th level, you can reroll a saving throw that you fail.

There are almost certainly more options that I've missed - getting advantage on things is a pretty fundamental part of 5e.

When you have advantage or disadvantage and something in the game, such as the halfling's Lucky trait, lets you reroll the d20, you can reroll only one of the dice. You choose which one.

If you roll a 1 you can use the Lucky trait to reroll that die.

Beginning at 9th level, you can reroll a saving throw that you fail. If you do so, you must use the new roll

If you fail the saving throw (with or without triggering Lucky) you can still only reroll one dice because the first quoted rule applies to this too. This can also trigger Lucky but not if the first roll did - that would be using Lucky twice on the same roll.

For your specific example, the 1 would trigger a reroll for Lucky. As this is free there is no reason not to use it. Irrespective of the reroll the 2 is almost certainly cause a failed save. Based on the reroll, you could then decide if spending Indomitable was a good investment.