7 Days to Die

Rewrite the solution for detail step to unlock fast without attention for both players

Prerequisite
1. A boosting partner (both can get by below method)
2. Stone Axe (Wood, Stone, Plant fibre)
3. 500 wood
4. Lots of Wooden Club
5. Some food (you may look for the center of the map with greenfield area)

Step-by-step guideline
1. Create a private game

2. Change the option: No zombie, minimum hardness (such that you craft much faster), any other option doesn't really matter

3. Invite your boosting partner

4. Once both join the game, click "Menu" > Player then click "+" from one player and accept for another player. Check the box to show the coordinate

5. Craft a stone axe, collect some plant fibre (it's everywhere) to craft some bedroll and place it regularly (in case you die suddenly, you can respawn on your bed), craft around 500 wood (use stone axe to craft a tree which should take no more than 30 seconds if you set the hardness to 25)

6. Find some foods (I found it's easy for some corn at center area near 950N, 530E which has a house as well)

7. Find each other and stay inside a house

8. Place bedroll nearby for both player

9. Player 1 start use the wood collected and craft maximum of wooden club (it take 5 wood for 1 wooden club, you should get 100 in this case)

10. Player 1 wait until all wooden club filled up you backpack and belt (which you can bring along with you), the crafting will stop as there's no available space

11. Player 1 select the wooden club and aim at player 2 head

12. Note: You may need to press "Menu" > Player and click "-" to mark both players not ally anymore as default setting avoid you hurt ally

13. Player 1 kill Player 2 (if you use wooden club and aim at head, it take around 30-35 damage per hit which make it 3-4 hits for 1st kill and the maximum health become 70 which take only 2-3 kills)

14. Player 2 press A to re-spawn on bed, IMPORTANT: Once respawn, long press Xbox button and disconnect controller (as now Player 2 can go take a nap), if you plan to grind it for 2500 kills in one go, make sure the console is not auto turn off by going to setting > Power section

15. Player 1 move and aim at Player 2 head

16. Player 1 use the rubber band to hold RT, connect your controller to Xbox to avoid auto-sleep for controller, it should kill Player 2 in 3-4 hits.

17. Once player 1 wooden club is used, as it will empty one available space, the crafting will start again and automatically create another wooden club so the process will keep looping

18. Per my experience the process on two console, it take around 20 secs for each kill and i.e. 3 kills per minutes, 180 kills per hours, so for all killing achievement, it will take 33 mins for 100 kills, 2 hrs 46 mins for 500 kills, around 14 hrs for 2500 kills.