Players can lose the game by losing all of their cards or life, but taking 21 damage from the Commander also counts as a loss
Beyond this the synergies are subtle and tend to only involve a few cards, for example Chandra's Phoenix improves Lava Dart, the few creature pump effects improve Spikeshot Elder, Mogg Fanatic and other creature sacrifice effects improve Brimstone Volley and the things that give haste work really well with Keldon Marauders
Niko, Light of Hope Niko, Light of Hope is a 2/3 human wizard that already makes two Shards, which are upgraded enchantment Clue tokens
Showcase your favorite Magic: The Gathering Commander (EDH), Pokemon, Lorcana, Flesh and Blood, or standard size TCG deck with Showcase Deck Box
Serah Farron's last ability checks at the moment it would trigger to see if you control two or more other legendary creatures
What I really like is that theres no alternative casting cost, so you can use this mana to pay for an overloaded spell