WARNING: This article contains spoilers about past and future episodes of Arrow.

Arsenal’s shocking departure. Trouble between Felicity and Ray. Ra’s al Ghul’s brutal determination to make Oliver Queen his heir. If you’ve been watching Arrow, you’ve no doubt noticed how the shocking plot twists and unexpected character decisions have kicked into overdrive as the season skyrockets to a close. Considering the show’s history of signing off each year with a bang, this isn’t unexpected for Arrow. But what is surprising is where the show’s final four episodes will take its characters, particularly its titular hero.

After last week’s shocking final scene, Oliver finds himself willing to do anything to save the life of his sister—even agreeing to join the League of Assassins. And if you think this choice will be followed by a quick escape from Nanda Parbat, think again.

With so many questions spinning out of recent episodes and so few remaining episodes this season, it seemed like the perfect time to ask Arrow showrunner Marc Guggenheim about Season 3’s final act. Here are his thoughts on five things still to come this year on Arrow.

Lazarus Pits

We’ve seen and heard references to Lazarus Pits, but tonight’s episode, “The Fallen,” is the first episode where we actually hear them referred to by name. After Ra’s al Ghul’s attack on Thea, Oliver has no other choice but to use the pit to save his sister’s life.

We’re all comic book fans,” Guggenheim says. “We certainly recognize the story potential of the Lazarus Pit and the interesting nature of it. We had a hunger for it.”

That means that fans can expect the Lazarus Pit to adhere closely to what they’ve seen in the comics. Use of the pit comes at a serious price, something that becomes obvious the moment Thea emerges from it. But tonight’s episode only scratches the surface.

“You can expect that there will be more consequences,” warns Guggenheim. “We establish very clearly that the Lazarus Pit returns you, but not always in the condition in which you left. There’s a lot of story still left to be told with Thea and her recovery.”

The Moment “Olicity” Fans Have Waited For

Yes, THAT moment. It’s coming and it’s arriving sooner than you may realize.

“There was a strong desire to have Oliver and Felicity sleep together before the events of the season finale,” Guggenheim explains. “We wanted to almost take that off the table prior to the season finale. We went back and forth on the right venue. Does it happen in Starling City? Does it happen in Nanda Parbat? They end up sleeping together in Nanda Parbat and I think we all sort of liked the romance of that. I’m personally fond of the fact that it’s Ra’s who gives Felicity the final push.”


A Team Arrow…Minus the Arrow

Yes, we saw a bit of this earlier this season when the team thought Oliver was dead. But Ollie’s decision in tonight’s episode changes things drastically for the remainder of the season, something that Guggenhein cryptically hints at, “Next week’s episode is a villain-of-the-week episode, but it just so happens that the villain is Oliver.”

The Arrow’s future is anything but certain, making what’s ahead for his teammates that much clearer—they’ll have to get used to operating without Oliver.

“In Episode 310, they thought he was dead and in many ways, that was a whole lot easier,” says Guggenheim. “Knowing that he’s out there and alive, but a member of the League of Assassins, that’s a whole lot harder.”

“What happens in the wake of ‘The Fallen’ is there’s a real trinity formed between Laurel, Diggle and Felicity. They’re all sort of leaning on each other. They’re processing things in different ways. Laurel is throwing herself into her work saving the city. Felicity is struggling with heartbreak and grief—she really goes through the seven stages of grief with Oliver. As for Diggle, something happens that really upends Diggle’s world. That’s something that will have repercussions for the remainder of the season.


An Important Choice for Maseo

Oliver’s friend-turned-assassin has played an important role all season long, but exactly how important becomes clear in the episodes ahead as the events in this season’s flashbacks finally reveal how Maseo wound up joining the League of Assassins. But does that mean he’s a villain?

As Guggenheim describes it, “I would say his soul is very much in play. In the past and the present there’s a little bit of a war for Maseo’s soul. With him joining the League of Assassins, we know how that war ended in the past. But how things end in the present and whether or not he can be redeemed is definitely one of the questions that we’re building up to answering.”


Some Closure for Thea

Guggenheim promises that Colton Haynes will be back as Roy Harper once more this season, to allow his character a chance to say goodbye to Thea, something that he wasn’t able to do last week. But that’s not all.

“By the end of the season, there’s a nice bit of closure between Malcolm and Thea,” promises Guggenheim. “You feel like their story has had a beginning, middle and end.”

Episode 20 of Arrow, “The Fallen,” airs tonight at 8 p.m. (7 p.m. CST) on The CW. The season finale of Arrow, “My Name is Oliver Queen,” airs on May 13, 2015.