: If Frodo is a Citizen, it becomes a Halfling Scout with base power and toughness 2/3 and lifelink.
: If Frodo is a Scout, it becomes a Halfling Rogue with "Whenever this creature deals combat damage to a player, that player loses the game if the Ring has tempted you four or more times this game. Otherwise, the Ring tempts you."
Frodo is a one-mana alternate win condition: pump him into a 2/3 lifelink Scout, then into a Rogue who, once the Ring has tempted you four times, kills any player he connects with. The deck spends early turns leveling Frodo, stacking Ring temptation triggers, and protecting/enabling a single combat strike to instantly eliminate an opponent. In between, lifelink and Ring-bearer evasion keep you alive while you assemble the kill.
Built-in, hard-to-interact-with win condition that can kill out of nowhere on turn 4-6
Extremely cheap commander (MV 1) that's easy to recast and abuse with Sam, Loyal Attendant
Ring temptation grants evasion (can't be blocked by bigger creatures) and card advantage, helping connect
Lifelink Scout stage stabilizes you against aggro while you set up
BW gives premium removal, recursion, and protection to clear blockers and shield Frodo
The kill requires four Ring temptations AND combat damage—needs setup and a clear attack
Single-target removal or a chump blocker easily delays the win; Frodo is a magnet for hate
No evasion of its own beyond the Ring; gets stonewalled by deathtouch or wide boards
Mana-intensive to fully level Frodo (WB WB then BBB) in addition to casting it
Color identity lacks fast blue/green interaction and ramp, so it can be slow