Attacking with Tajic and playing a creature post-combat causes him to protect himself from spell damage until your next turn.

I've also experienced Tajic not working quite as intended.

He's working a little too well!

I'm not entirely sure how to reproduce this, because sometimes, my opponents spells DO damage Tajic, but other times, there spells fizzle as if he's protecting himself.

If I were to venture a guess, it may have to do with summoning another creature after the attack step.

Tajic's ability proc's on attack, and you can see the visual protection get applied to everyone but himself... But, after combat, if I summon another creature, Tajic's ability happens a "second" time, and his buff is also added to the new creature. Maybe during this second time of his buff getting applied, somehow it's also getting applied to him? Does it have to do with the "creature positions" on board? Because, adding a new creature to the board might shift around what position Tajic is listed at? And, somehow that's allowing his buff to get applied to himself?

Anyways, it's definitely a bug. But, since I've been the one playing Nahiri, it's been nothing but upside for me! Yet still, my opponents deserve better.

Many bugs with creature effects that don't work as intended :

1. Tajic, Legions Edge - supposed to prevent spell damage to other creatures you control after attacking. What is actually happening is he also prevents spell damage to himself. So I used a lightning helix on him hoping to finish him with a shock, only to find my lightning helix ineffective and then I lose off course due to wasted spell and turn.

2. Counterfeiter and Virtus the Veiled - effect should only trigger after dealing combat damage. However, effect is actually triggering even with 0 attack power as long as they get through.