There and Back Again has exactly two lore counters on it.
Steps
At the beginning of your precombat main phase, There and Back Again triggers, putting a lore counter on it.
There and Back Again's third chapter ability triggers, creating a legendary 6/6 Smaug creature token and causing you to sacrifice There and Back Again.
Activate Ghired by tapping it, creating a copy of the Smaug token.
Put either Smaug token into your graveyard due to the legend rule.
When the Smaug token dies, it triggers, creating fourteen Treasure tokens.
Activate three Treasure tokens by tapping and sacrificing them, adding ({1} magic symbol) ({G} magic symbol) ({U} magic symbol) .
Once you have infinite mana, you may instead use Ghired to copy any other token(s) that entered the battlefield under your control this turn, and/or use Lilysplash Mentor to blink any other creature(s) as desired.
Results
Infinite LTB.
Infinite ETB.
Infinite colored mana.
Infinite death triggers.
Infinite blinking.
Infinite Treasure tokens.
Infinite copies of tokens you control that entered the battlefield this turn.