Pixel Strike 3D

The 5th consecutive Daily Reward unlocks when you boot the game up everyday for 5 days in a row. This means that going offline and changing the date 5 times will not work because most of the game's nature is online based.

This achievement is tricky as sometimes the game fails to register your log in, here's a guaranteed way to ensure you get to that 5th day:

Dont touch the game for 2 days, this allows the reward timer to start when you open up the game again

Open up the game at a time you feel comfortable with/are free

Once you open up the game you should receive a menu with the first reward, take note of the time, for me I did this at 7pm eastern, play one full round of any game mode, try to get a task done

For the next following days, log in 2 hours prior, play one competitive game AND one casual game, make sure you complete a task

Once the time you took note on comes around, open the game up again 3-5 minutes after the time, it should pop up, take note of the new time and repeat for the following days

There probably is an easier way to archive this but this method worked for me

Good luck!