Here, the pronunciation would be exactly the standard soft gamma, much like the English "y". Gamma is normally soft when followed by epsilon, iota, or ypsilon, and hard when followed by alpha, omicron, or omega. It's analogous (not identical) to the English practice of hard or soft c or g: soft before e or i, hard before a, o, and u.
Gamma also changes pronunciation in a couple of combinations of consonants. The double-gamma sounds like the "ng" in English "wing": "αγγελικος" - angels. The normal hard gamma is not the same as the hard English "g", but the combination gamma-kappa is.
It's a y sound, like in "Yay!" before ε, ι, or υ, and like the gh in "ugh" but voiced (g is voiced k, d is voiced t &c.) before α,ο, or ω and <γγ> is pronounced like the ng in English, but not the <ng> in sing. <γκ> is pronounced like the hard g sound. (This is basically sdr51's simplified)