Midfielder Marcel Langer says "it was not really a hard decision to make" after signing a six-month deal with Hearts after being released by Schalke.
The Edinburgh club had hopes to add Barnsley forward Mamadou Thiam and Celtic goalkeeper Craig Gordon but both deals failed to transpire.
Huddersfield Town were also interested in the Scotland international but Celtic were not willing to let the 37-year-old leave this month.
His contract expires in the summer.
Langer, meanwhile, has already worked under Hearts manager Daniel Stendel.
"When I played in the youths for Hannover 96, I worked with the manager in the U19s," the 22-year-old said.
"We were really successful. We won the U19s German Cup. It was a good connection."
The German had been playing with Schalke's second string since his switch to the top-flight club in summer 2018 and will now move permanently to Hearts.
"I like adventures," Langer told Hearts' website. "It's a new country, a new city and a new language. I'm looking forward to it and I'm happy."
Frenchman Thiam also worked under Stendel at Barnsley, having signed from Dijon in his homeland in 2017, but the 24-year-old made the last of his nine appearances for the Championship side this season in September.
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