Match three or more, but remember: a ghost will repeat your move on the same cells turns from now.
Swap adjacent gems to line up three or more of a colour and reach the target score within your move budget.
Swapping adjacent gems to line up three of a colour is the match-three puzzle, the form Bejeweled took to a mass audience in 2000.
The original element is the replay: your past moves come back, so the board is partly authored by what you already did.
Match-three is normally played entirely in the present — the board is whatever it is and history does not exist. Making earlier moves recur turns a reactive game into a planning one, because a swap is also a thing you will have to live with again.
Echo Match turns gem-matching into a planning puzzle by replaying your past moves. It is an original free browser game built in-house for PlayPendium.