An upgrade of Power Tool Dragon and the last of the Signer Dragons from Yugioh 5D's, this card is a nice addition to a lot of synchro decks. It's also the highest level tuner monster that I'm aware of, which makes it a prime target for Battle Tuned.
As a monster, Life Stream Dragon boasts high attack, sitting at 2900, which is enough to keep itself safe from most monsters. If that wasn't enough, it has an effect that prevents its destruction by removing an equip spell in your graveyard from play. And, last but not least, when it's summoned, you can make your life points become 4000, which is useful if you use cards that make you pay life points to use them, like solemn Judgment and Solemn Warning, or as an attempt to keep yourself afloat against a tough opponent.
Strategies and game play:
As a Tuner, Life Stream isn't good for anything on its own other than high level Synchro monsters, like Shooting Quasar Dragon. It's usefulness goes up greatly if you use cards like Level Eater, Mischief of the Yokai, or Star Siphon to drop its level and make it more usable as the Tuner it is.
However, if you don't want to use it as a tuner, it's other effects make it very useful on its own. If you were to summon this card after summoning The Winged Dragon of Ra, you can make your LP 4000 after paying it all to his attack, which will keep you in the game longer and even enable you to use its destruction effect.
Another thing you could do is use this card in a burn deck, to keep your burn effects from hitting you, as it prevents effect damage from going through.
Combos with other cards:
This card can combo well with cards that deal effect damage to both players, like Chain Burst, or Dark snake Syndrome, keeping you from taking the damage from those cards and making your opponent take the damage while you sit safe and sound. It could also combo very well with Level Eater and other cards that lower the levels of monsters on the field, making way for synchro summons with it.
It also can be used with Battle Tuned to give a 2900 attack boost to a monster, being the strongest tuner in terms of attack.
Ways to counteract it:
Like most cards, it's easy to stop, with the right cards on the field. Dark Highlander and Solemn Judgment in the Traditional Format, Solemn Warning when its summoned, Effect Veiler or Divine Wrath when its effects go off, or an attack when there are no Equip Spells in the Graveyard.
Can be a life saver with its effect to make LP 4000 when summoned
Can't be destroyed if there's Equip Spells in the Graveyard
No effect damage can hit its controller.
High Level tuner for use with Battle tuned, which can give a 2900 attack boost to a monster.
High level tuner means that without effects, it's difficult to Synchro summon with him
Like Power Tool Dragon, it needs Equip Spells to keep itself alive, and without them it's an easy target for destruction effects and high attack monsters.
It comes in ultra Rare and Ultimate Rare versions in both the TCG and the OCG in the Extreme victory Booster pack.
Artwork and aesthetics:
Aesthetically, it looks like Power Tool Dragon had an organic makeover, which ties into the fact that it's synchro material requires Power Tool Dragon. The screwdriver from Power Tool has changed to a sort of pile driver looking weapon, to go with the equip spell effect.
I'd have to give this monster a 6.5 out of 10. Its high level means that it can't be used as synchro material for anything less than a high level monster like Shooting Quasar Dragon without another effect like Level Eater or Star Siphon, but it's effects can be a life saver in a tight situation, which makes it playable without the need to use it for a synchro summon.