At the beginning of your end step, Jon Irenicus triggers, causing an opponent who controls no Swamps to gain control of Bog Serpent.
Bog Serpent triggers, causing the opponent to sacrifice it.
However, Bog Serpent cannot be sacrificed due to its ability granted by Jon Irenicus.
Bog Serpent triggers again, creating a mandatory infinite loop that causes the game to end in a draw.

Draw the game

Jon Irenicus, Shattered One

Bog Serpent

If necessary, at the beginning of the upkeep of an opponent who controls no Swamps, Assault Suit triggers, causing that player to gain control of Bog Serpent and untap it.
Bog Serpent triggers, but cannot be sacrificed due to Assault Suit's ability.
Step 2 repeats forever, resulting in a mandatory infinite loop that causes the game to end in a draw.

Combos with "Bog Serpent"