The 27-year-old Newcastle United midfielder was the 11th and final signing of the summer for the ambitious Tigers.
Special dispensation was needed from the Premier League to get the deal over the line to take Hull’s number of captures on deadline day to four with Abel Hernandez, Mohamed Diame and Gaston Ramirez having earlier joined the Yorkshire club.
On his new signings, Bruce said: “They are all highly talented. Hernandez is going to be a really exciting one for the supporters. He is going to be the main striker for Uruguay in a few days’ time, and they are ranked sixth in the world.
“We have got the experience of Diame, who has been in the Premier League for the last six years, and is a player we know all about.
“Ramirez is a very skilful footballer and unfortunately for him, it hasn’t turned out as he envisaged at Southampton.
“And the icing on the cake was Ben Arfa, a little bit of a maverick. We all know he is a wonderful talent and although it has gone a little bit sideways for him at Newcastle in the last couple of months, he will bring that little bit of flair and creativity that every team needs.”
Hull’s outlay in the transfer window edged towards £40m on the final day, a sum that was partly offset by the departures of Shane Long to Southampton for £12m and George Boyd to Burnley for £3m.
Bruce added: “Again, the big pat on the back has to go to the people that employ me. When we were having discussions about the sale of Shane Long a few weeks ago, they said it wasn’t a problem to reinvest the money we received.
“There is a real trust there between them and me and the supporters that we’re going to do the best that we possibly can.
“They have proved that again with what we have been able to do in this transfer window. Now it is up to me to make sure that the players gel together and get us up and running. I think we have done some fantastic business.”