The Falcons will kick it off Thursday night in Philadelphia with visions of a home Super Bowl dancing in their heads, and while a dream akin to Christmas with family may be in play, they’d better hope to miss a booby-trapped acronym under the tree.

Look out for Philly’s RPO.

The Falcons slogged in their last real game, scoring only 10 points in Philadelphia’s January chill, yet the game remained close right down to Matt Ryan’s failed throw toward Julio Jones on fourth-and-goal from the 2 in the waning moments.

The Falcons slowed Philadelphia big-time, but these do not appear to be those Eagles, who scored 15. Perhaps the Falcons changed them.

Philly blew up after their meeting, whipping the Vikings 38-7 in the NFC Championship game and then dethroning the Patriots, 41-33 in the Super Bowl.

Their somewhat new-fangled offensive, dollar-store stocking stuffer suddenly turned into a confounding, gold-plated toy for the ages.

The Eagles ripped off 79 points in their last two postseason games not because they added personnel, but largely because they tweaked their run-pass option offense, turbo-charging a newish NFL concept shop-lifted and grown from the college ranks.

“They call it free plays, free yards. That’s how they look at the RPOs,” Falcons defensive coordinator Marquand Manuel said. “The ability to go from first-and-10 to second-and-3, just based on ... if they create a (defensive look) that you might be playing the run or you might be playing the pass, then they have seven yards (doing the opposite).”

This is a good time for an RPO tutorial.

While it’s not new to the Eagles, who ran RPOs on 18 percent of their offensive snaps last season, second only to the Chiefs’ 18.1, this is recent to the NFL.

It goes like this: The offensive team lines up – usually in what looks like a run formation – and after the quarterback makes a pre-snap read of the alignment of the defense, he makes more reads right after the snap, like an option quarterback.

Foles will be looking in these situations at more than he would in a straight read-option play, where more often than not the (option) QB is checking the play-side defensive end to see if he’s crashing – in which case he keeps the ball and runs outside – or taking a wide rush – in which case he hands the ball off to a back running the tackle/end gap.

Foles will read the defensive end, play-side linebacker, play-side safety and even the cornerback. If he sees a linebacker or safety creeping forward for run, or a corner crashing inward – he will not hand off or pitch the ball to the back.

He’ll throw a fast pass.

It has to be quick because part of the RPO design calls for offensive linemen to show run block, and if the QB waits too long to make a play decision, the risk rises that linemen will get far enough downfield that if the QB throws, the linemen will be penalized for “illegal men downfield.”

So, on most RPOs, offensive linemen slide left or right as if on kickout blocks rather than straight forward on standard drive blocks.

“The thing about the RPO which makes it so hard for a defense to defend is because when the offensive linemen are running sideways ... you can’t tell the difference between a run or a pass,” Falcons free safety Ricardo Allen said.

Manuel said, “I’m going to talk to the refs (before the game), too. You have to make sure the linemen are not downfield.”

Wide receivers – or whomever splits out – have to be ready to run block. And they run short routes, to make quick catches if the plays becomes a pass.

Where the read-option often relies upon the running ability of a quarterback if he keeps the ball, the RPO relies more upon the speed with which a quarterback can make multiple decisions quickly rather than run quickly.

Athletic ability at the quarterback position helps, but more important is his processing speed.

“I clearly remember back when San Francisco started it with (Quarterback Colin) Kaepernick and ... he had some big games doing that and that kind of lit it up for a while,” Falcons coach Dan Quinn said. “Now the RPO version is without having to be a mobile quarterback, you can still use the guy’s ability to read and see a (defender’s) leverage (inside or outside].”

One of Foles’ key reads will be strong safety Keanu Neal, who often sets up in the run box.

The RPO generally seeks to take advantage of defenses that load the run box, show a run formation to make the defense further commit, and then keep alive the opportunity to spin an in-play audible – a pass.

Philly grew the concept in the NFC Championship game and in the Super Bowl.

The Eagles added bubble screens, and slant routes where defenders got picked off by crossers. Rub routes.

It’s also possible that Foles and Philly will tilt a play hard one way, and the Falcons overflow toward that side, and the quarterback puts on the brakes and keeps the ball to run up the middle.

There’s yet another twist.

Everything may start as an RPO with most of the offense sliding right or left. Then, quickly, the offensive linemen retreat into traditional pass-protection, the quarterback peels backward into a rolling pocket, and receivers bust double moves and go deep.

With adaptations in the Philly offense, Foles completed 26 of 33 passes against the Vikings for 352 yards and three touchdowns. Against the Patriots, he completed 28 of 43 for 373 yards and three more scoring passes.

Minnesota and New England defenders often seemed to have little idea what was going on.

It won’t help the Falcons that Philadelphia tight end Zach Ertz is one of the NFL’s best at his position. He’ll be covered at different times by linebacker De’Vondre Campell, Neal, Allen and occasionally nickel back Brian Poole.

“We’ve got to be disciplined. We’ve got to read our keys and play the ball,” Neal said. “If you’re in man, and he releases, you’ve got to stay with him. ... He’s very detailed in his route running. He knows how to manipulate. He knows how to use his leverage.”

“Manipulate” and “leverage” are key words. The other is “read.” That’s on the quarterback.

Atlanta defenders would be wise to not believe that because they slowed the Eagles in January that slowing them Thursday night will be easy.

Philly is different now.

“It never rolls over,” Allen said of one season vs. the next. “You can figure that because you stopped somebody in one game . . . sometimes you play the same divisional teams and you stop them the first game and they can run the same stuff and they do it a little better. You just never know.”

Yeah, that’s the point of the RPO.