Riker is the sixth offensive lineman to transfer to the Nittany Lions this offseason.
Campbell was named to the All-Big Ten Third Team in 2025.
Alexander has three years of eligibility remaining.
McDaniels has three years of eligibility remaining.
Smith played under Matt Campbell at Toledo from 2012 to 2013.
Taupaki is the second former UCLA defensive linemen to follow Ikaika Malloe to Happy Valley.