What happens in The Flash crossover episodes, stays in The Flash crossover episodes.

Oliver: "Malcolm, could the League of Assassins help us with Hive?"

Laurel: "Hey, did you ever install any extra security systems to keep say Malcolm Merlyn from just strolling on in here or get that armored limo for Oliver and Felicity like we asked for since it's pretty likely Darkh will eventually will just straight up try to assassinate them at some point."

Hamill really did slide back into that Joker voice from JL which added a nice touch.

And gloss over being able to "enlarge the image" to see it in Tricksters pupil. I mean, at least STAR Labs might have programs/processes to make that not laughable. Patti was just like, yup, I totally see that doll from my childhood in his pupil. That's why I'm an amazing detective! Flash who?

Joe: "Guess I no longer have to worry about not being there for my son!"

Barry: "Iris, what's wrong?"
Iris: "I'm keeping a secret from my Dad and it's eating me up inside!"
Barry: "Pffff I live on keeping secrets from the people I love. I'm 90% certain they power the speed force or whatever. I'm riding the not telling Patti I'm the Flash all the way till next year baby!"
Iris: "You're the…

I imagine the League of Assassins jumps through the windows for practice. Merlin likes to keep his daughter "safe"!

Oliver: "You know what I love about this apartment. These huge glass windows, so we can look out over the city while we have drinks with a person we're trying to protect even though that seems like a pretty big vunerability. I'm so glad you got them fixed Speedy after the last time an assassin/super villian crashed…

Cisco: "Don't tell Kendra I have super powers. I don't want to scare her off."

Just imagine, every date Cisco goes on with a super hot woman, he kisses her and immediately vibes she's a metahuman/ancient Egyptian Princess/god/whatever.

Henry Allen: "Yeah, I was camping by myself in Granite Peak, went fishing every day all by myself. You know, doing father/son bonding things you'd think a father and son would do after the father just got out of jail after 15 years. What have you been up to?"

Can't blame Cisco for keeping his powers a secret. He's witnessed first hand the inhuman (sorry, wrong show) living conditions those STAR Labs cells are like. Or it's karma for not installing toilets in the cells. He either ends up in there or, more likely, dead. Being a metahuman kindof sucks if you're not the Flash…

Cisco can McGyver a freeze gun in an hour but his video glasses don't offer full color HD picture?!?!?

Flash: "Guys, maybe we should have talked about how I'm going to defeat Dr. Light for maybe a sec or two."

"Mrs.Snow I've been looking for you! Even though why I decided to look for you here, in a random mechanic's garage seems strange since there is no way for me to know why you'd be here." - Henry Hewitt

"Guys, I've created a portal between worlds! It's this large black obelisk that only works when the planets align *just* right and for about 30 seconds or however long a man who's in love with a woman needs to rescue her.

"I'm Tina McGee, President and CEO of Mercury, my time is far too valuable to waste talking to two detectives, so I'll just let them poke around because they seem experts on all this stuff. Oh, why don't we have any security footage from the break-in? We're using the same security company that STAR Labs uses. Security…

Jay Garrick working in a lab, sees Harrison Wells lurking around STAR Labs.

Brett on Archer had that super power.