Taken a big challenge with this and I’m predicting it’ll take a while to finish.

Black, grey, blue, white, red and green (for background) dk yarn from stash (had to buy more white, grey and green)

Working solid granny square 2 rounds in size.
Black: 139
Grey: 92
White: 113
Blue: 51
Red: 1
Green: 254 = 650

So glad to have finished this. It stalled for a while as it got tedious making all the green squares needed to finish. I definitely recommend sewing squares on each time you have enough for a couple of rows.
For the border I worked rounds of sc crochet to finish; two in white then one in blue then two more in white.