You've got the whole spectrum of stag party activities to indulge in. Zagreb stag dos can do the classics such as Paintballing and Go-Karting, or strike out and try something different.
Try Caving, Rafting, Fishing, Cycling, Hiking and Golf to name but a few. Thanks to the forests and mountains, there are tons of outdoor pursuits to sample. After a day spent in the great outdoors, everyone will no doubt need to refuel to prepare for a classic Zagreb stag night.