This is an 11" x 17" promotional, color poster, custom double matted to a 15 1/2" x 20 1/2" size for season 1 in 2021 of the TV series, Loki.  The poster has been autographed by the following:
 
Tom Hiddleston- Loki
Eugene Cordero- Casey
Jonathan Majors- He Who Remains
Frank Grillo- Crossbones
Sasha Lane- Hunter C-20
Michael Waldron- Creator for television
 
They all signed in silver felt-tip pen with the exception of Sasha Lane who signed in black, felt-tip pen.
 
The poster has been independently authenticated by SWAU, a reputable autograph and authentication company. Their sticker is on the bottom right of the poster.  In addition, you will receive a certificate of authenticity from TinkerBellTalks.com with a lifetime guarantee on the authenticity of the autograph or a full refund would be made.