Prominent among these are the literally hundreds of times Trump promised that Mexico would pay for his proposed wall, not the American taxpayer. Then, within days of the 2016 election, he was changing his tune and talking about how the wall cost would be reimbursed indirectly via trade deals.
Equally, Trump's promises about the scope and construction of the wall has shifted in terminology, too. He has engaged in considerable backpeddling since the election and thus abandoned scores of prior promises.
The way Trump so cavalierly and resolutely makes promises he has no intention of keeping makes you wonder if he really understands how the internet works. At the same time, his near constant lying is always thoroughly documented, so Trump's lasting legacy will be that he was fundamentally dishonest.