To get combo at 8th turn you need:
1st turn: put depleted power.
2nd turn: put depleted power.
3rd turn: summon Time merchant to get Journey Guide from market.
4th turn: summon Journey Guide, after that 1 Primal/Shadow merchant to get Reccuring Nightmare with decreased cost by 1.
5th turn: summon Time/Primal merchant to get Nesting Avisaur from market.
6th turn: summon Nesting Avisaur and put Reccuring Nightmare on topdeck.
7th turn: summon Fire merchant to get Iceberg Scattershot from market.
8th turn: summon Iceberg Scattershot, summon Reccuring Nightmare over 9000 times.
As i said, i like combos, but i just don't judge the deck to be a viable option.
P.S. Journey Guide is useless after turn it summoned. You already reduce Nighmare's cost at 4th turn.