There are three paths for TA explorable and you will be given the choice to chose after you defeat the Greater Nightmare Vine Boss, they are Up, Forward/Up, and Forward/Forward.
Up path is the one most commonly farmed as it has rather easy bosses but hard trash. Forward/Up is the second easiest path but the bosses are slightly more difficult. Forward/Forward path is in my opinion massively overtuned with very difficult trash and boss fights. You can do the Up and Forward/Up path daily to get 60 tokens in about 1 hr with an experienced group.
Most of the boss fights are fairly straightforward but if you are stuck on a particular fight or just want to read more on the dungeon I do have a rather lengthy guide that I wrote here. It discusses the bosses for all three paths (with videos if possible) and some tips and tricks here for clearing the trash.
- Introduction (Path selection, Deadly Bloom farming, Dealing with blossoms)
- Shared path (Greater Nightmare Vine)
- Path 1 (Malrona, Fyonna, Nightmare Tree w/ Leurent)
- Path 2 (Leurent elite guards, Leurent, Nightmare tree w/ Vevina)
- Path 3 (The Defiler, Vevina, Nightmare tree w/Fyonna)