Whereas morphs like Stratus Dancer and Apprentice Voidmage simply counter spells when turned face-up, Kheru Spellsnatcher counters a spell and steals it for later use, which can completely swing a game in your favor depending on what spell the Naga snatches

Aberrant Mind Sorcerer Abomination of Llanowar Accomplished Alchemist Advocate of the Beast Aether Herder Aftermath Analyst Ajani's Comrade Alisaie Leveilleur Allosaurus Rider Allosaurus Shepherd Alpha Guard Alphinaud Leveilleur Ambush Commander Aragorn and Arwen, Wed Arbor Elf Arcane Investigator Architect of the Untamed Argothian Elder Armorcraft Judge Armored Wolf-Rider Arwen Undmiel Arwen, Mortal Queen Arwen, Weaver of Hope Astarion, the Decadent Atomwheel Acrobats Attended Socialite Aurora Champion Ayara, First of Locthwain Ayara, Furnace Queen Ayara, Widow of the Realm Baeloth Barrityl, Entertainer Beast Whisperer Beast-Kin Ranger Beastcaller Savant Behemoth's Herald Belbe, Corrupted Observer Bennie Bracks, Zoologist Birchlore Rangers Blaring Recruiter Blightsoil Druid Bloodbraid Challenger Bloodbraid Elf Bloodline Shaman Bloom Tender Borderland Explorer Boreal Druid Boreal Outrider Boss's Chauffeur Bramblewood Paragon Branchblight Stalker Brazen Upstart Briarblade Adept Brightwood Tracker Caller of the Claw Caller of the Untamed Canopy Tactician Carapace Forger Cautious Survivor Celeborn the Wise Celebrity Fencer Centaur's Herald Champions of the Perfect Chance-Met Elves Circle of Dreams Druid Circle of the Moon Druid Citanul Stalwart Civic Wayfinder Cloakwood Swarmkeeper Coiling Oracle Compleated Huntmaster Conclave Guildmage Copperhorn Scout

Kaldra Compleat managed to push things a bit farther in both directions, in that it was a stronger equipment to put into play, but it was also even harder to cast on its own
In the meantime, you CAN look forward to catching em all when Pokemon Red, Blue, and Yellow come to 3DS on the same day, February 27, 2016
Im a firm believer that Commander players like to struggle, and by that, I mean they work hard to make their concept or plan succeed
As far as Pokmon abilities go, you can attack with 50 damage and get bonuses