broken card or bug?

[izlude123]

is this interaction intended or is it some kind of bug abuse ?
dude put 2 x offspring cleric
dude find a way to gain life 1 time and the effect reapeated itself until i die

[Traumaturgy]

Its infinite combo of "Whenever you gain life, each opponent loses X life" and "Whenever an opponent loses life, you gain that much life. "

So Bloodthirsty conqueror and Starscape Cleric / Enduring Tenacity, or similar cards.

[Kolarahidumgarabashtelarimdugarn]

As above: there are multiple cards that can trigger this combo. If you played against bats, then it's probably because of Sanguine Soothsayer that can create Sanguine Bond. The second card was probably Enduring Tenacity.