'Go to Deal' takes you to The Master chief Collection where you can click on the individual games.
Halo: Combat Evolved(store.steampowered.com)
Halo 2: Anniversary(store.steampowered.com)
Halo 3(store.steampowered.com)
Halo 3: ODST(store.steampowered.com)
Halo: Reach(store.steampowered.com)
Halo 4(store.steampowered.com)
Borderlands 3(store.steampowered.com)
Thanks OP