Reliquary Tower makes sure you wont have to discard any of your good cards
A deck like Syr Gwyn, Hero of Ashvale or Greven, Predator Captain loves this
This card is sort of the Tooth and Nail of lands, while the other three abilities are used based on whats best for you
It makes a decent lord for decks that churn out Thopters via cards like Sai, Master Thopterist, and the lack of a once per turn restriction lets you do some wild stuff with mass Treasure production
You'll want to keep creatures off the board for aggro decks and be wary of spells during your turn for control decks, but this gets all the more difficult to track depending on how your opponent handles their first few turns, too
Its important to note that just activating the regeneration ability doesnt exactly mean the creature has been regenerated. The oracle text makes it clear that this gets a +1/+1 counter when it regenerates , so it still needs to die in some way for regenerations replacement effect to actually resolve