Time for me to get involved. Hold my beer.
Lands that enter tapped slow your deck down immensely, and because you're playing a Mardu aggro strategy, the last thing you want is to be slowed down (I'm pretty sure that going fast was the whole gimmick behind the Mardu clan).
If we're talking high-risk, high-reward, the lands you're currently using are not that. It's more like high-risk, low-reward.
Hall of the Bandit Lord, is high-risk, high-reward.
Gamble is high-risk, high-reward.
Necropotence is high-risk, high-reward.
Kabira Crossroads is not.
But that's enough of that. I want to really help
flesh out this deck. What direction do you want to take this deck? Are you trying to make it pure-combat damage, combo-centric, or something in-between? Have you tested this deck out? And if so, how did the games go? What parts did it excel at, and where did it struggle?
Also... I'm not seeing all the combos here either. What are they?