Obviously I have nitpicks with individual cards -- I've been yelling about Temple of the False God only being good in decks that reliably land ramp and it's especially bad in decks with lots of color pip requirements -- but these are just nitpicks
The 30th Anniversary: Gaboleps Gauntlet Stepping back a bit out of order for a moment, our penultimate entry is an Arcane Signet that keeps on giving
The downside is still a Goblin Electromancer that occasionally pings you for damage, but the upside is flipping this planeswalker into Ral, Leyline Prodigy, a fairly tame walker that preserves the front side's cost reduction and adds in some other forms of disruption
Plus, in Commander, cards that incidentally gain life are very powerful
If a player or permanent has more than one kind of counter on it, and you choose for it to get additional counters, it must get one of each kind of counter it already has