Goblin Welder + Retreat to Coralhelm + Ancient Den
Combo result
Infinite white mana. Infinite red mana. Infinite landfall triggers. Prerequisites
Ancient Den in your graveyard. All other permanents on the battlefield. Goblin Welder does not have summoning sickness.
Tameshi, Reality Architect + Mind over Matter + Ancient Den
Combo result
Infinite mana permanents you control can produce. Infinite landfall triggers. Infinite self-discard triggers. Infinite untap of permanents you control. Prerequisites
Darksteel Citadel in hand. All other permanents on the battlefield.
Tameshi, Reality Architect + Sculpting Steel + Ancient Den
Combo result
Infinite landfall. Infinite storm count. Prerequisites
Sculpting Steel in hand. All other permanents on the battlefield.