OK, so this is what we currently have:
Mark of GRAVITY
This deck is much too cluttered, and needs to be trimmed down to 30 cards. Most importantly, it needs to have FOCUS.
Let's take out all of the Death cards so that we're down to a solid duo-deck. We'll use Gravity as the main element and Earth as the support.
We know that unupgraded Otyughs need some help with their health statistic before they can devour, so we'll keep the Plate Armours. The Sapphire Chargers ignore shields, so they'll stay.
Colossal Dragon is too slow and clunky, the Gravity Pulls aren't really needed when you have Otyugh for creature control, Momentum isn't really needed when you have the Chargers, shields are generally unnecessary when you're fighting AI3 and only slow you down, and Black Hole doesn't fit the theme of the deck too well, so they'll all have to go.
In their place, we'll add a few copies of Earthquake for quantum denial, re-balance the pillar count, and change the mark to Earth so that we can include fewer Stone Pillars but still cast the Earth spells more quickly.
In the end, we'll have something that looks like this:
Mark of EARTH
If you want to use this deck for top 50, remove the Otyughs and Plate Armours for 4 Black Holes and 2 Earthquakes, and swap one Gravity Pillar for a Stone Pillar.
Experiment with and modify your deck to suit your own taste -- you might come up with the best thing since Rainbow decks and sliced bread!