Big W is running 20% off Lego as part of Click Frenzy for 2 days (starting Wed 25/5/22).
If you're after some Lego set, you might want to compare (Target is also running 20% off, but depend on the set their RRP might be lower/higher than Big W).
Also, some of their set are already 20% off on their ebay store ahead of time, so if you want to stack with some other offer like ebayplus or Shopback's ebay offer, you might want to look at their ebay store (you might be able to use certain ebay voucher too). I'm not sure if that's unintentional from Big W as usually their ebay store is in line with their main store (and a couple of set on my watch list was 20% this morning but then revert back to RRP now).
Thanks OP! Kids birthday and xmas presents will be sorted.