What is the running problem?
Simply put, it is easier to run away from your opponent's attacks than it is for them to attack. This results in a degenerate strategy where a player will attempt to gain a trivial health lead and then evade the rest of the match until the timer runs out. Before the "win by health" condition was added to the game, players would run away if they were at low health in order to force a draw.
Why is running so successful?
In Wands, players must decide how best to divide up their limited mana pool for spell casting. The runner can spend 100% of their mana on Teleport or other evasive strategies. Meanwhile, their opponent needs to chase them around the arena and somehow still have mana left over to attack. This puts the chaser at an automatic mana disadvantage. The strategies the chaser can use to gain the upperhand are limited and require much more nuance to accomplish than running, which is relatively straightforward.
How should it to work?
A game that favors offense (where damage is difficult to avoid entirely) tends to naturally resolve matches with a definitive KO. By comparison, games that favor defense tend to result in ties/tiebreakers. Generally, you can use the amount that offense edges out defense to tune how long matches generally take before one players kills the other. If your matches are taking too long, make offense more powerful. If matches are over too quickly, scale back the offensive power.
What existing methods are there to mitigate running?
Strategy - Utilize spots that have LOS with as many other spots as possible and you won't need to spend as much mana giving chase.
Level design - Maps with high connectivity make it easier to attack a runner without having to spend mana on giving chase.
Spells - Spells like Meteor or Phoenix let you attack around some corners without having to spend mana on giving chase (sensing a theme?). Traps like Spikes let you block off hiding spots or punish careless Teleporting. Using spells cheaper than Teleport can force a mana advantage you can exploit.
Peer pressure - Painting runners in a negative light on discord has encouraged community members to voluntarily avoid this strategy.
Isn't that enough?
Despite these factors, running has been a constant issue since the game first came out and isn't likely to go away unless there are significant changes.
Ok, so how do we fix it?
My proposal is basically to add a separate energy meter for mobility (similar to the Stamina bar in other games). If Teleportation has its own dedicated resource then runners can't trade mana away for more running power and chasers always have the same amount of energy set aside to keep up with them without losing their ability to attack.
Note: Chaos Leap would also cost Mobility energy, as would any other movement type spells added in the future.
My current thinking is that this energy resource is used for mobility spells only and that defensive spells would still cost mana. This would mean that a runner could switch to defensive spells like Shield or Dome when they are out of Mobility energy, but I think that is ok because these spells tend to have interesting and balanced counter strategies (Dome may still be a little powerful). It is interesting to contemplate the ramifications of having a separate resource for ALL defensive spells (Teleport, Leap, Shield, Dome, Armor)....but I don't think this is the right approach atm.
A big change like this would have some ripple effects that would need to get worked out, but I think the benefits are potentially huge for the fun factor, pacing and finality of duels.