The objective of the game is to kill all units that are coming for your fort .

的目的，游戏是要杀死所有的单位，来为您的炮台。

youdao

Units that kill a further 3 times their own value gain the "Elite" rank. Elites have 20 more health and deal 20 more damage.

再次杀死三倍于自己价值得单位可以升级为“精英”等级。精英们拥有20%得额外血量和20%得额外伤害加成。

youdao

Units that kill a further 3 times their own value gain the most feared "Heroic" status.

再次杀死三倍于自己价值得单位可以升级为令人畏惧得“英雄”状态。

youdao

As for the top 5, I honestly could not see XCom being the great game it was, considering how unbalanced the gameplay is in single-player, especially when certain units like Sectopods require blind luck to kill.

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