Worlds from this series of soft-cover stories:

 

A-Chiltar III
A’askavariia
Aakon
Achernon
Aedi
Aerie
Alfheim
Alpha Centauri
Ankara
Annoval 14
Arago-7
Archeopia
Arcturus IV
Ardent Spring
Argor
Arima
Ariston
Armechadon
Asgard
Astra
Asylum

Ba-Banis
Badoon
Battleworld
Berhart (alternate spelling of Berhert?)
Beta
Biphasia
Birj
Birkeel
Blackworld
Breakworld
Broi

Calculex
Calurnia
Carmondy IV
Centauri IV
Centurri-Six
Ceres
Chandilar
Ciegrim-7
Clarius
Conjunction
Contraxia
Counter-Earth
Cron
Cyber

Dakkam
Darbia
Deo
Dervani
Drez Lar
Dyofor

Earth (a.k.a. Midgard) —*Note:  While depicted as the middle/center of Yggdrasil, that is only from its own point of view.
Easik
Ego
Elanis
Entem

Femizonia

Galador
Gunava

Hala
Halfworld
Harokin
Hiberlac
Horus IV
Huj

Interdis

Jhb
Jotunheim
Jupiter

Kakaranathara
Kallu
Kitson
Korbin
Kosmos
Krelar
Krylor

Lar
Laxidazia
Lemista
Lumin

Maklu IV
Maarin
Marvan
Maveth (where the alien tentacles-head Hive came from, who Inhumans on Earth honored by starting a secret society for… which eventually became Hydra)
Mercury
Mobius
Moord
Morag
Muspelheim

New Xanth
Nidavellir
Niflheim
Nix
Nornheim

O’erlanii
Oorga

Paramatar
Power Planet 4
Praxius IX

Quon

R’makl’z
Ria
Ryas

Sakaar
Sirius III-IV
Skrullos
Sovern (alternative spelling of Sovereign?)
Sszardil
Stent
Stonus I-V
Strontia
Svartalfheim

Taa
Tarnax IV
Taur
Tayp
Tekton
Terma
Timor
Titan (moon)
Titan II
Torfa
Tsorcherhi
Tun

Vanaheim
Vega Superior
Vormir
Vrelnex

Wilamean
Wobb-Lar
Wraithworld
Wundagore II

X (where Groot’s tree-humanoids come from)
Xandar
Xanth

Zen-Whoberi (Gamora‘s race/homeworld)
Zenn-La

 

Details here.

coming:  pics of the planets listed above –and comic book pages about them