Take a Look at the bullet points below for a quick reference of what to expect:
The Doom tower consists of 120 main floors, a boss is positioned every 10 floors. These bosses rotate on a month by month basis in terms of positions.
You have two types of keys, gold keys are for normal progression through the tower, you are awarded 10 gold keys per day per reset. Silver keys are used for replaying (farming) boss fights and secret rooms. Keys will only be subtracted from your account once you clear a floor. If a failure occurs and you do not complete the level, the keys will remain in your account, much like faction wards.
Neither gold nor silver keys can be purchased in any way. There’s opportunity to farm more keys over 10, however once reset occurs you will be reset to 10 gold and 10 silver keys.
Bosses you face on every 10 floors of the Doom tower will scale according to the level you are on. I.E if you face one boss on level 20, and the same boss appears on level 80, it will be much more difficult than the first time around.
Secret rooms pose a different type of challenge, some secret rooms will contain challenges. I.E only uncommon or a certain faction to be used to beat the secret room.
The doom tower is on a rotation, every 30 days the tower will reset both Normal and Hard mode, including rotation of the bosses you have faced throughout.
A total of 12 secret rooms are available throughout the tower.
A total of 12 boss stages are available throughout the tower.
Rewards scale dependant on how far through the Doom tower you are. The higher you get, the better the rewards.
Resist the temptation for secret room farming until you are further up the tower. Better rewards are available as you progress higher up the tower. For more efficient farming hold onto your urges!!
Every time you do secret rooms you get awarded with silver keys. Meaning it is more beneficial to wait until you are higher up the tower to ensure better rewards.