These are the three I own myself: Front one is a Machop, the other two are Red Cheeks Pikachus: Greetz, Quuador geg89 August 2, 2017, 2:40pm 4 Ahh thank you
Efficiency can be determined simply by the reward you receive at certain mana costs (Counterspell and Cancel do the same thing, but Counterspell costs less), the total payoff you receive from a single card (Hull Breach and Decimate are both good cards, but Decimate usually covers much more ground), or the payoff you receive in conjunction with other cards (Anointed Procession makes other token production cards completely absurd if unchecked, which is usually better than adding one more card that simply makes tokens like Spectral Procession in a token strategy)
The archetype that Sliver Swarm focuses on entirely is Combat: the deck provides tons of cards that greatly increase its effectiveness in combat, from dishing out extra damage with Bonescythe Sliver to providing evasion with Cloudshredder Sliver to drawing card on combat with Synapse Sliver
This is an example of a card that is too good at what it does, and it invalidates counterspells/removal by its very existence
(2022-10-07) If another player gains control of your graveyard, Animate Graveyard will be put its owner's graveyard