It will remain in effect until the game ends, the target creature leaves the battlefield, or some subsequent effect changes the creature's characteristics, whichever comes first
Second Harvest does something that every token-themed deck wants: get more tokens
Heres a few more notes: Damage of any kind and direct life loss to any opponent activates spectacle, and it does not matter who dealt that damage or how the life was lost
The way you get around this is by cheating it into play, either by reanimating it early on or putting it from your hand into play through other means
Despite his heavy use as a Commander, his reduced usage outside of the Command Zone drops him to the 3rd spot on my countdown, but, again, I see all here of these as worthy of the top spot
Tinkaton EX: 160 DMG from only 1 heads