20. Don't Stop Believin' (Rachel Solo Version) Episode: 04x19 "Sweet Dreams" Sung by: Rachel Why it slays: Feels everywhere. Goes back in memory of the New Directions' first ever song together, just not as good as the original cover. It was also Cory's last performance. R.I.P.
19. Teenage Dream (Acoustic) Episode: 04x04 "The Break Up" Sung by: Blaine Why it slays: Also not as good as the original cover in Season 2, but it's still great. I loved how he actually sang on the show and in acoustic style, too. It also went very personal with the tears.
18. Locked Out of Heaven Episode: 04x11 "Sadie Hawkins" Sung by: Marley, Unique, Tina, Sugar, Brittany Why it slays: Simply an enjoyable, fun bop, just like the original. Everyone slayed in this.
17. Let's Have A Kiki/Turkey Lurkey Time Episode: 04x08 "Thanksgiving" Sung by: Isabelle, Kurt, Rachel Why it slays: The most random mash-up of all time. But for some reason, it worked and it was hilarious in the process, especially when Rachel switches the song.
16. You're the One That I Want Episode: 04x06 "Glease" Sung by: New Directions Why it slays: Everyone did so well in this, and seeing Finchel perform it as well (and more feels with that flashback) was amazing.
15. A Thousand Years, Pt. II Episode: 04x12 "Naked" Sung by: Marley, Jake Why it slays: Just as beautiful and romantic as the original. Both of them absolutely shine in this.
14. Hall of Fame Episode: 04x22 "All or Nothing" Sung by: New Directions Why it slays: They perform this so well as a group and the song really releases all the struggles they had to get through to be at Nationals.
13. Everybody Talks Episode: 04x05 "The Role You Were Born to Play" Sung by: Jake, Kitty Why it slays: Both of them were really amazing in this. Together they made a very energetic and fun performance that can actually make you like them as a couple.
12. We Will Rock You Episode: 04x20 "Lights Out" Sung by: New Directions Why it slays: I love how they took this classic and made the beat with various objects. Mostly everyone has a part and everyone sounds great when it's their turn.
11. I Still Believe / Super Bass Episode: 04x16 "Feud" Sung by: Blaine, Sue Why it slays: Jane Lynch, a 53-year-old, tall, white woman dressed as Nicki Minaj rapping to Super Bass. That's really all I have to say. Forget about Blaine's part fff, he's irrelevant in this. Both impressive and hilarious.
Don't Stop Believin, Teenage Dream, LOOH, We Will Rock You,
Hall of Fame, A Thousand Years, Pt. II & Everybody Talks
Not a huge fan of Glee but i love their covers!
But for some reason, it worked and it was hilarious in the process, especially when Rachel switches the song.
Also yes and Zedd and Ariana on your newcomers list! 
Never really used Harlem Shake, wasn't ever my cup of tea.
and that epic Gaga performance!
