Dallas Mavericks owner and fellow billionaire, Mark Cuban, has been going at Donald Trump hard through this election season, and at times, it has been hilarious.

This is one of those times, because I’m having a blast with this.

The two, and their surrogates, have been at it for months. But the latest spat, over the Republican nominee’s proposed border wall with Mexico and detention centers for undocumented immigrants, comes amid on/off rumors that Cuban might act as a surrogate for Trump during Hillary Clinton’s preparation for their first presidential debate.

Perhaps that’s why Cuban has taken to trolling Trump for details on his plans. For all his bluster about the wall, Cuban noted, Trump hasn’t provided any architectural or financial infrastructure for the project that has been the cornerstone of his campaign for the highest office in the land.

While trolling, certainly, they’re also legitimate questions. We already know Mexico has no intention of paying for a wall, despite the lies Trump is so comfortable putting out to his cultists. He can do that because they will believe whatever he says, no matter how logistically unsound.

Cuban later went on to speculate about Trump’s taxes and why the GOP nominee is so reticent to release them, in spite of there being no legal reason to prevent him from doing so.

From trial depositions, Cuban showed that Trump often uses limited liability (Subchapter S corporations) companies in his construction business.

When Trump’s lawyer, Michael Cohen (He, of “Says who?” fame) became involved, accusing Cuban of paying trolls to harass Trump, Cuban didn’t back down, and it was awesome.

He also went at Cohen over rumors that the lawyer was fired by Trump’s campaign.

Have I mentioned lately what a great place the internet can be?