The scroll of rigour was a members-only reward that could be purchased with 140,000 Dungeoneering tokens earned through the Dungeoneering skill. It required both Dungeoneering and Prayer levels of 74. Once used, this scroll would disappear, giving the player the ability to use the Rigour prayer, which, at the time, increased their Ranged attack by 20% and their Defence by 25% while active.
Purchasing the scroll required 140,000 tokens. Obtaining tokens solely through the completion of dungeons would put a player at level 77. At level 74, the additional tokens could only otherwise be earned by completing the Nadir saga 12 times (on different days).
After using the Read option of the Scroll of rigour, the item would disappear and the following message would appear in the chat: The secret is yours! You read the scroll and unlock the ability to use the Rigour prayer.
Currently the Rigour prayer only requires a Prayer level of 70 as well as completion of the Knight Waves training ground, and grants the player 8 bonus Ranged levels when calculating hit chance, 8 bonus Defence levels when calculating block chance, and an 8% boost to ranged damage dealt.