Tekuthal has at least one indestructible counter on it, and at least one +1/+1 counter on it.
Steps
Activate
Tekuthal using
Myojin of Towering Might's ability by removing an indestructible counter from it, putting five +1/+1 counters on
Cryptic Trilobite, and three +1/+1 counters on any creature you control.
Activate
Cryptic Trilobite's first ability twice by removing two +1/+1 counters from it, adding ({C} magic symbol) ({C} magic symbol) ({C} magic symbol) ({C} magic symbol) that can only be spent to activate abilities.
Activate
Tekuthal by paying ({3} magic symbol) and removing three +1/+1 counters from
Cryptic Trilobite, putting an indestructible counter on it.
Repeat.
Results
Infinite colorless mana that can only be spent to activate abilities.
Infinite colored mana that can only be spent to activate abilities of creatures.