Here is the full list of all 10 Hammer Kid achievements.
Collect 30 Red Gems
Kill 10 Snakes
Collect 10 Red Gems
Collect 50 Green Jewels
Complete the first level.
Collect 500 Green Jewels
Collect 100 Food
Collect 50 Coins
Collect 1500 Green Jewels
Collect 100 Red Gems