Hi Guli,
nice original approach. Inusual cards, but strong in your shell. However I find it prone to card disadvantage with those 7 one shot mana critters. I suppose you focus on mana screwing: 8 strip lands, 4 surgicals, 4 thalia, 3 null rod, 3 revoker. but what if they have enough basic lands? or if they drain a hate card and have the extra mana? Can you win a game when the opponent has no mana problems?
on the other hand, cavern makes humans easier to get into the battlefield, so thalia and confidant (being the strongest imho) must be killed instead of countered. Sniper seems a nightmare to snapcasters, revokers, confidants, welders... Just feel a bit dependant to confidant
are you playing this deck in competitive environments?
No, someone asked me some help regarding a budget deck in the current metagame. So I started working on a budget version of my Human Cavern deck and this was the result.
Note that there are also Shardless Agents and A Tandem Lookout next to Dark Confidant to get board presence and tempo. The spirits are only one shots but there are 9 cards that generate card advantage. Not to mention the virtual card advantage Thalia, Sniper, Mayor and Revoker can generate.