Looking for and to help with Halo Achievements.

I’m looking to clean up Achievements in a few Halo games as I’m wanting to 100% them.
I’m also looking to help people out with Achievements they need help with.

Gamertag: DarkraiNewmoon
I’m mostly on in the evenings. My timezone is GMT (UK)

For Halo 3: I need both Zombie/Infection achievements Delicious Brains & Zombie Repeller.
I also need Post Mortem and Vidmaster: Annual.

For Halo 3 ODST: I need both Vidmaster: Endure & Vidmaster: Deja Vu.

For Halo Wars 2 and HW: Definitive Edition: I only need the Campaign Co-Op achievements.

For Halo 5: I just need to finish Co-Op and score attack Achievements.
I need a majority of MCC’s matchmaking achievements and co-op stuff in the campaigns.

I’m willing to help out other people with their achievements as well, just ask.

I also need help with some of these. I will add you. My gamer tag is shackos