Untap, upkeep, Draw, Mountain, Giant Trap Door Spider, Done.
Oversoul: 7
Hand: 1
Library: 47
In Play:
-(U, U, U) Island x3 (Train's favorite card)
-(U, U) Underground Sea x2 (U/B dual land)
-(T) Grim Monolith (Doesn't untap as normal; T: 3; 4: Untap)
-(U; 25/25) Mistform Ultimus (11 counters...