BUYING/SELLING AND SHARING ACCOUNTS
Players must not share, transfer or lend their account to anyone else. You may have as many game accounts as you like, but each account should only be used by the person who created it. All game accounts are the property of Jagex and players are only granted limited permission to use accounts. Nobody has our permission to sell accounts.
If you buy an account, it’s likely that the seller will take it back from you after you have already put time, resources and effort into it.
For another player to use your account they will require your login details. This means your account security is weakened. If you allow somebody else to access your account they might steal items or Gold (GP) from you or even try to claim the account belongs to them so they can keep using it forever. In addition, if they cheat or break our rules using your account they could get your account muted or banned for things that you haven’t done.
Sharing accounts is also a form of cheating. This is because sharing an account with somebody else gives you an unfair advantage. Completing challenging achievements and appearing on the HiScores is recognition of individual effort, and should only apply to players who stick to the rules and play fairly.
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The above from ‘
Rules of RuneScape
’ I have highlighted in here because what you are asking is a ‘
form of sharing account details
’ … meaning … you wanna share yours RuneScape Authenticator with/over 2 devices instead of 1 device.
Who is going to check if those 2 devices are your personal devices and who is going to check if you do not share one of both devices with someone else?