On the end step prior to your turn, activate Bloom Tender by tapping it, adding at least ({W} magic symbol) ({U} magic symbol) ({R} magic symbol) ({G} magic symbol) .
Activate Mistmeadow Witch by paying ({2} magic symbol) ({W} magic symbol) ({U} magic symbol) , exiling Realm Razer until the beginning of your end step.
When Realm Razer leaves the battlefield, its second ability triggers, returning the exiled lands to the battlefield tapped under their owner's control.
At the beginning of your end step, Mistmeadow Witch triggers, returning Realm Razer from exile to the battlefield.
When Realm Razer enters the battlefield, its first ability triggers, exiling all lands.
Repeat.
Results
Exile all lands opponents control during each of your turns.