well the secret room can be found at every 5 floors counting 1-4,5-9,11-14,... that and if u take heal and then max battle tree and focus on defence nothing damages u add 20 mana regen tada ur close to invincible
i found a way to OP myself the combination is: a range rune, absorb( an overpowered artefact that allows u to absorb clouds into power), a cloud rune and a random blue rune to make it healing
and then u can spam ahead it will give u lots of power just dont kill urself like i did
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