Any card that lets you give control of that permanent to an opponent or force them to make a copy of it puts them under an alternate loss condition, which is a roundabout way to win the game
Instead of boosting power and toughness as a static ability, this Elf Warrior creature features a mana sink (and what a sink it is, with an activation cost of ) that boosts the power and toughness of all of your Elves by two while tacking on deathtouch
(He probably made four new decks since I started writing this article.) We tried to persuade him to use real card names for a while, but he ended up writing Glaivemaster for Auriok Steelshaper and Voltron for Auriok Glaivemaster, which was worse than whatever he was doing before
This is easy enough to do, considering any self-respecting proliferate deck will have tons of permanents that enter with counters on them already
Starting from turn two we ideally want to play our enablers, so having a way to get rid of the opponents hate card on turn one is huge
But for this precon, the choice is obvious: this is a Knights precon and Sidar is the Knights commander