Intruder Alarm and Jungle Patrol on the battlefield.
Jungle Patrol does not have summoning sickness.
Creatures you control can tap to produce at least ({G} magic symbol) .
({1} magic symbol) (at most) available.
Steps
Activate all mana-producing creatures by tapping them, adding at least ({G} magic symbol) .
Activate Jungle Patrol's first ability by paying ({1} magic symbol) ({G} magic symbol) and tapping it, creating a 0/1 Wood creature token.
When the Wood token enters the battlefield, Intruder Alarm triggers, untapping all creatures.
If needed, activate Jungle Patrol's second ability by sacrificing the Wood token, adding ({R} magic symbol) .
Repeat.
If creatures you control can tap to produce at least ({1} magic symbol) ({G} magic symbol) , this combo nets infinite mana, and you may forego sacrificing the Wood tokens.