Those single cards can be played around with sufficient metagame knowledge and preparation
Whenever it attacks, you can toss any of your other creatures or artifacts into its cannon, and fire them out at any target you choose for big damage
It synergizes with other cards which do gain you life, including a card youll see on the list: Exquisite Blood (more on that as we discuss the card)
It is unlikely to ever hit more than a few things as well as Chandra would probably not be around let alone loyal enough to fire off a one sided Inferno
Boss's Chauffeur Far Fortune, End Boss Forge Boss Greasefang, Okiba Boss Hammerhead, Maggia Boss Hellspur Posse Boss Krenko, Mob Boss Legion Warboss Phabine, Boss's Confidant Racketeer Boss Raggadragga, Goreguts Boss Steamflogger Boss
Other blink cards such as Flicker can also target enemy creatures (though not at instant speed), which can be a very valuable play at the right time