I was struggling a bit with G wave HBM.
So why did I struggle to beat 5 G waves.
Some of my heroes tend to die in first waves. Reason: they went too far behind walls and attracted enemies.
How to avoid this? Bases 2 and 4 are for ranged heroes. In my case Cupid and GR. Bases 1 and 5 are reserved for heroes with AoE (TG and Immo) because they had to deal with griffins. Druid is always and without doubt in the middle (base 3).
Why GR? GR is better for this, even 20 levels lower than Champ or Succubus. First, he is ranged and is not running behind walls. Second, he is targeting more enemies than Succubus and much faster than both Champion and Succubus. Even lack of his movement speed is not such a disadvantage on relatively small space as my base is.
PS: Thanks for major help with my base goes to Doktor2a.