As long as there are four or more lore counters among Sagas you control, Tom Bombadil has hexproof and indestructible.
Whenever the final chapter ability of a Saga you control resolves, reveal cards from the top of your library until you reveal a Saga card. Put that card onto the battlefield and the rest on the bottom of your library in a random order. This ability triggers only once each turn.
Tom Bombadil is a five-color Saga-matters commander: deploy Sagas, advance their lore counters, and when a Saga hits its final chapter, chain into another Saga off the top of your library for free. You snowball value while Tom becomes hexproof and indestructible once four-plus lore counters are on the battlefield, then convert accumulated Saga payoffs into board dominance or a combo finish.
Free, repeatable Saga chaining generates massive card and tempo advantage every turn
Becomes hexproof and indestructible with minimal setup, making him a resilient value engine
Five-color identity unlocks the entire Saga pool plus the best ramp, fixing, and removal
Sagas provide built-in card advantage and removal stapled to a single permanent
Variance: the chain reveals Sagas randomly, so you cannot reliably tutor the chapter you need
Heavy reliance on the command zone—if Tom is countered or kept off the battlefield the engine stalls
Sagas sacrifice themselves, so a sweeper-light board can leave you with little permanent presence
Five-color manabase is demanding and the deck can be slow to set up
Doubles lore counter placement, accelerating every Saga toward its trigger-fueling final chapter.
Add counter-doublers (Doubling Season, Vorinclex, Hardened Scales effects) so Sagas finish in one turn and immediately trigger Tom and his hexproof. Tighten the manabase with fetches, shocks, and Triomes plus fast mana like Mana Crypt and Jeweled Lotus to deploy Tom earlier. Prioritize Sagas that double as removal or ramp so every chain link advances your board rather than just digging.