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Most of the time it is combo decks that play this however I have seen it used in control decks although a word of warning on this front, unless you have some way of clearing up the board like an Upheaval or Austere Command you are not really achieving anything with it

Its just a symbol that gives you another way to pay for a spell or ability

Myutant Ultimus X DARK Level 10 [ Psychic / FusionEffect ] ATK 3500 DEF 3000 3 Level 8 or higher "Myutant" monsters When a card or effect is activated (Quick Effect): You can banish 1 "Myutant" card from your hand, GY, or face-up field, of the same type (Monster, Spell, or Trap)

If youre not on the play but this land is in your opening hand, it enters with a luck counter and starts to tap for any color of mana immediately, which essentially gives you a head start