This is a weird but cool tower.
Here are my thoughts:
Name: Eldritch* Aquarium
* Or similar word to make it sound old, mysterious, and maybe glowing. I don't remember details from the Cthulhu stories, but they could provide some inspiration.
Give it some damage so it could be useful. Maybe range 2, 30-40 damage, 3 second delay.
Skill 3 shouldn't be on the card. Instead it can grant that benefit silently.
If the aquarium gets damage, then instead of skill 4, then use a different skill 4:
Either:
Give +5% damage per eldritch item in play.
Or:
Eldritch items on the aquarium are +2% more powerful for each eldritch item on the map.
(Mr. Iron can eat a lot of eldritch items, so these bonuses shouldn't be too big.)
Edit: if we call it Eldritch Aquarium, would that mean its damage and skill bonuses would double with Dagon? Is this a good thing? It would be interesting if Dagon made this a viable carry. For non-Dagon players it would just be a support tower like Acolyte of Greed.
