Crumbling Berg

Fading 5
{t}, Remove a fade counter from Crumbling Berg: Add {c} to your mana pool.
When Crumbling Berg leaves play, exile it. If you do, add X+3 blue mana to your mana pool & tap X+1 nonblue creatures. Unless they are snow, they don't untap during their next untap phases. X equals the number of fade counters remaining on it.