President Trump Tuesday mocked Democratic 2020 front-runner Joe Biden for lacking energy, suggesting the former vice president looks like he has aged.

“I don’t know what the hell happened to Biden,” Trump said. “What happened to him? I’m looking, I said, ‘That doesn’t look like the guy I knew.’ What happened to him?”

The president compared him to Vermont Sen. Bernie Sanders, who he said seemed more robust, albeit crazy.

“And Bernie – you know, Bernie’s crazy. But Bernie’s got a lot more energy than Biden, so you never know,” Trump said. “Bernie’s got a lot of energy, but it’s energy to get rid of your jobs — the opposite energy that you produce. Not good energy. You don’t like his energy.”

Biden on the campaign trail has appeared frailer and has garbled his words more than previously.

[ Opinion: Byron York: Joe Biden and restoring the old (pre-Trump) order]

Speaking at an event in Hackberry, La., promoting his energy policy and the economy, Trump took shots at several of his Democratic competitors, starting with Pete Buttigieg — "I got boot edge edge" — and ending with Elizabeth Warren.

He also said sarcastically that he liked the looks of his 2020 Democratic competition.

“You sort of dream about competition like that, but who knows,” he said, sparking laughter from the crowd.

“I got Beto. Beto’s falling fast,” the president said. “What the hell happened? Remember four weeks ago, he said, ‘I was made for this.’ He was made for it. He was made to fall like a rock. What happened to him? But he’s tried to re-start his campaign. That generally doesn’t work out too well.”

Beto O’Rourke faced heavy criticism for remarks that were published in a Vanity Fair article in March. The Texas candidate, who lost a Senate race against Republican Sen. Ted Cruz, apologized Tuesday for his comments.

Finally, the president took a dig at Massachusetts Sen. Elizabeth Warren, who has been accused of over-emphasizing her distant Native American ancestry for professional gain. The candidate released a DNA test earlier this year that revealed she was between 1/64 and 1/1,024 Native-American.

“Pocohontas, I think, is probably out,” Trump said. “Boy, you got some beauties here. Three-hundred-fifty million people, and that’s the best we can do.”

There are currently 22 Democrats in the crowded field. Montana Gov. Steve Bullock, the newest contender to jump into the race, announced his candidacy Tuesday morning.

[ Related: Trump welcomes 'Sleepy Joe' to the Democratic primary race]