Goblin staff 25 damadge, 1% knockback and crit. medium speed. Goblin sword 20 damadge 3% Knockback and crit, fast speed plus autoswing. Goblin bow 21 damadge 5% crit and knockback medium speed. Feel free to see if I missed something
The rewards should be well distributed between all four damage types. By the way, rangers already have this.1 the goblin staff, 2 goblin bow, 3 goblin sword