Time Bomb

Indestructible, Cannot be Exiled
Enters with 5 time counters
Remove a counter at the beginning of each upkeep
Each opponent may pay {5} to put a counter on
Time Bomb on their upkeep
If an opponent attempts to take
control of Time Bomb,
All counters are removed and destroys
all non-land permanents they control
If Time Bomb has no counters on it
the controller wins the game