Former Hearts and MK Dons striker Osman Sow has moved to Rugby Park on loan from Dundee United until January.
Scotland U21 internationalist Harvey St Clair arrives on loan from Italian side Venezia - the 20-year-old forward was previously with Chelsea.
Defender Connor Johnson is a loan signing from Wolves - the 21-year-old has had previous loan spells at Boreham Wood, Telford United and Walsall.
