I found out an interesting way to get full usage out of Gib, being my Main Tower in my last run - Victory
I made a Scientist/Bunny Start-up, swaped both to lucky shadow drops at wave 9.
I added two herb witches and (with immense luck) had a full frozen set on wave ~50.
I started to experiment with Gib, doesnt found a real usage.
But I was wrong. I swapped him for my lv35~ shadow, then equipped him with a Messerschmidt Reaver, Excaliber and 2 Rare T-Bones.
He got an Essence of Wisdom, ToG, Nillo's strange whatever it shall be (pardon, I am new to this :)) and voila.
I pumped every single potion in him and voila.
His Icing Armor for creeps were negated due to a lv30 knusperhexe.
Other Towers were Ganesha and herb witches only, with 3 fistful of steel, 2 herb witch cauldrons, and few other lucky drops. :)))
Gib ended up in lv92.
Ill try it again and provide Screenshots.