Gateway is a Codex entry featured in Tom Clancy's Rainbow Six Extraction. It is unlocked by killing three different Protean variants.
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GATEWAY Protocol guidelines: Classified Top Priority Level Alpha.
Confidential for Operator Eves Only. Due to the highly unusual and dangerous circumstance of this objective, the Operator(s) must act swiftly and initiate tactical directive TD-A01, which states: By Any Means Necessary.
The Operator(s) will travel through the GATEWAY, locate the Protean within the Singularity and eliminate it. (Cross-Ref: Protean, Singularity)
To enter the Singularity, the Operator(s) must initiate the release mechanism for the GATEWAY and remain within its radius until transference is complete.
It is not recommended that any Operator(s) initiate the GATEWAY without ensuring they are fully prepared. The Protean may have enhanced or empowered abilities and is often aided by Archaean swarms.
Please remember, to follow Safety and Security Measures at all times but note the TD-A01 must be enforced.