In a chat with THR, the CW star previews Wednesday's sophomore closer and looks ahead to season three.

Can Oliver Queen topple Slade Wilson once and for all?

Arrow wraps up its second season with a finale that pits a former protege against his ex-mentor. Titled "Unthinkable," Wednesday's closer has Oliver (and a few of his friends) facing off against Slade and his Mirakuru army. Slade has vowed to shatter Oliver's world, a declaration borne mainly out of spite after Oliver "caused" Shado's death all those years ago on the island. Following Moira's death, Slade has his eye on one more victim in Oliver's orbit.

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In a preview chat with The Hollywood Reporter, Stephen Amell touts "the biggest fight in the history of the show," a not-so-deadly finale and hints at season three.

The entire season has come down to an anticipated showdown between Slade and Oliver. How would you describe this final battle?

There are two of them and that’s the coolest thing about the finale. In the middle of the episode, we have logistically the biggest fight in the history of the show. At the end of the episode, we have the climactic moments between Oliver and Slade both in the past and in the present. They intercut with one another. You can have all these big fights and big chases, but at the end of the day, what people are waiting for is Oliver and Slade to fight. Period. Just the two of them. That’s what we get in the finale. It’s awesome.

Oliver is getting some all-star help. How many superhero characters does it take to take down Slade?

It takes an army. We’re fighting an army and we need an army, so an army is what we bring, which is an actual line from the episode. The whole idea is that this is such a formidable challenge that Slade is presenting that we literally need an army. The cool thing for Oliver is relying on other people for help is not his strongest but he is absolutely, positively forced to accept anybody’s help if they’re offering. That’s a new thing for him.

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In the past, he’s gotten help from Canary and sometimes Roy, but here, he has to incorporate at least half a dozen others. Does Oliver play well with others?

This is the first time he’s embraced everyone else’s help. Obviously Felicity and Diggle are part of the team, but he needs to rely on Nyssa, he needs to rely on Roy.

With Sebastian Blood biting the dust last week, I imagine we’re not done with death. How deadly does the finale get?

Actually, not too deadly -- except for one moment that is shocking, only because it's so simple. It happens early in the episode. Oliver's M.O. all year has been not killing, whether or not he can hold back against Slade is the ultimate moment that we come to this season. It's not a particularly deadly finale.

Oliver has managed to stay on course this season with his vow not to kill. How close does he get to breaking that?

That's where we find ourselves in the finale. Can he follow through? How many things have to be sacrificed for him to stay on this course? That's what we examine in the finale and it takes Oliver to a place that's not necessarily to killing, but it's a place that he's never gone to before. It's measures that he'd never consider taking before.

With his mother's death and Thea potentially teaming with Malcolm, how has that affected Oliver? Has he even had time to think about that part of his life?

We don't really know yet. This will be our third episode since Moira's death and episodes 21 through 23 take place over the course of one night. Oliver doesn't even know that Malcolm's alive. He thinks Thea left Starling City. That's this gigantic elephant in the room. As far as Oliver moving forward without a family, ostensibly as an orphan, he hasn't had a chance to consider that yet because there's such a clear and present danger right in front of him.

Now that Laurel is in the know of his Arrow identity, has their relationship changed? Do you think it will?

They'll have their moment of trying to reconcile all of this new information. But it hasn't happened yet because it's been five hours since Oliver found out Laurel knew. They'll have their moment but it won't happen this season.

Katie Cassidy said recently that Laurel believes she and Oliver are "soulmates." Does Oliver share those same feelings?

Oliver's always going to love Laurel. He's always going to love her, period. But things change. Oliver never wanted Laurel to know for a reason because knowledge equals danger. The people that find out his identity always find themselves in the crosshairs of trouble. I think that her knowing, even though it's revealing Oliver to be the guy she always hoped he would be, at the same time, it may make it more difficult for them to have a relationship in the future beyond friendship.

Where do Felicity and Oliver stand in the finale? Will fans be happy?

Oh boy, I can't tell you that! (Laughs.)

What can you say?

If every Arrow fan sat down and tried to figure out where the finale would leave us, meaning city, place and time, nobody would get it.

Looking ahead to season three, it was revealed that Oliver had a child pre-island and pre-Queen's Gambit. How do you think he'd take the news if and when he finds out the woman didn't give up the baby?

I hope that's something we get to examine. I think we do a good job of resolving this season and leaving enough open threads that people will be excited to come back.

Arrow's season-two finale airs Wednesday at 8 p.m. on The CW.

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