I have done a whole pile of prestiges, leveled up companions, upgraded items, leveled up in tournaments, and I still keep getting stuck around stage 800 every time. I can get a little higher if I blow a ton of potions but still just can't seem to make real progress. Any suggestions? Particularly useful agents/agent combos to try? I've been there for weeks and weeks and am getting bored.
Depending on how many companions you already have, I'd say shoot for another one instead of upgrading. Any new companion can up your power a lot cheaper than upgrading a current one, depending on any current levels. I wanna' say it takes around 30k treats to upgrade a companion from 1 to 40, but I could be remembering wrong. Maybe that's to 30. But depending on what your costs for 1 upgrade are on your current companions, you may be better off saving and getting a new companion.
Also, on weaker strengths, you may wanna' focus more on a special ability instead of raw strength. For example, if Arcane isn't a strong power for you, instead of focusing on Arcane people, focus on stuff like idle gold and special ghosts.
There are three types of companions. The amount of treats for leveling varies for each type. They can cost 6,560 or 3,648 or 2,027 to upgrade level 1 to level 40. 40 to 50 can cost 30,860 or 13,949 or 6,247
I like using Solar and Nyx. And I have both of their items at the legendary level. Even if I'm doing an Arcane or Traditional run.
Using Blizzard in the later portion of a run (once the minion progress slows down) may be your best boost of DPS. Then when the trap duration is over, close the game for the cooldown period to get more idle gold to increase the agents.
It's hard to give solid suggestions on what to try without knowing what you've already tried. Doing an arcane run during tourneys is my best bet for advancement, but occasionally I forget what I'm doing and choose the wrong agent (other type specialty or other arcane agent.) If I do that early in a tourney, I may prestige as soon as I get to 101 and start over. But right now I'm at a tough wall in getting past 900 consistently.